# Patent

## Title
Compounds comprising a hibonite structure and a method for their use

## Abstract

Novel colored compounds with a hibonite structure and a method for making the same are disclosed. The compounds may have a formula AAl12−x−yMaxMbyO19 where A is typically an alkali metal, an alkaline earth metal, a rare earth metal, Pb, Bi or any combination thereof, and Ma is Ni, Fe, Cu, Cr, V, Mn, or Co or any combination thereof, and Mb is Ti, Sn, Ge, Si, Zr, Hf, Ga, In, Zn, Mg, Nb, Ta, Sb, Mo, W or Te or any combination thereof. Compounds with varying colors, such as blue, can be made by varying A, Ma and Mb and their relative amounts. Compositions comprising the compounds and methods for making and using the same are also disclosed.

## Background
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of International Application No. PCT/U.S.2015/017983, filed on Feb. 27, 2015, which claims the benefit of U.S. Provisional Patent Application No. 61/946,383, filed on Feb. 28, 2014, which prior applications are incorporated herein by reference in their entirety.


ACKNOWLEDGMENT OF GOVERNMENT SUPPORT
This invention was made with government support under DMR0804167 awarded by the National Science Foundation. The government has certain rights in the invention.


FIELD
This invention concerns hibonite compounds, particularly colored hibonite compounds, compositions comprising the same, and a method for making and using the compounds and compositions.
BACKGROUND
Blue inorganic pigments, such as cobalt blue (CoAl2O4), ultramarine (Na7Al6Si6O24S3), Prussian blue (Fe4[Fe(CN)6]3), and azurite (Cu3(CO3)2(OH)2), are known. However, these known compounds all suffer from environmental and/or durability issues. For example, prussian blue liberates HCN under mild acidic conditions, and ultramarine and azurite are not stable with respect to heat and acidic conditions. Additionally, commercial processes for making ultramarine produce significant SO2 emissions.
SUMMARY
In view of the above, there is a need for new, stable inorganic pigments comprising substantially environmentally benign and earth abundant components. Disclosed embodiments of the present application address this need and provide novel, colored compounds and a method for making and using such compounds. Certain disclosed compounds are synthesized blue hibonite compounds. In some embodiments the compounds have a formula I

AM12O19  I.

With reference to formula I, A is selected from an alkali metal, alkaline earth metal, rare earth metal, Pb, Bi, or any combination thereof, and M is selected from Al, Fe, Ni, Ti, V, Cr, Mn, Co, Cu, Zn Ga, Ge, Si, In, Sn, Mg, Zr, Hf, Nb, Ta, Sb, Te, Mo, W, or any combination thereof. As used herein, the term metal also includes metalloids.

Also disclosed herein are compounds having a general formula II

AAl12−x−yMaxMbyO19  II.

With reference to formula II, A is selected from Ca, Sr, Ba, Mg, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof, Ma is selected from Ni, Fe, Cu, Cr, V, Mn, or Co or any combination thereof, and Mb is selected from Ti, Sn, Ge, Si, Zr, Hf, Ga, In, Zn, Mg, Nb, Ta, Sb, Mo, W or Te or any combination thereof. In some embodiments, x is from 0.01 to less than 12, y is from 0 to less than 12, x+y is less than 12, and if y is 0 then x is from 0.01 to less than 1. In other embodiments, x is from 0.01 to less than 1, y is from 0 to less than 12, and x+y is less than 12. In certain embodiments, x is from 0.01 to less than 12, y is from 0.01 to less than 12, and x+y is less than 12.

In some examples, Ma comprises Fe and y is greater than 0, such as greater than or equal to 0.01 or greater than or equal to 0.1. Alternatively, Ma may comprise Fe and at least one additional metal selected from Ni, Cu, Cr, V, Mn, or Co. In other examples, Ma is selected from Ni, Cu, Cr, V, Mn, or Co or any combination thereof.
Ma may comprise at least two metals selected from Ni, Cr, Cu, V, Mn, Co or Fe, such as V and at least one additional metal selected from Ni, Cr, Cu, Mn, Co or Fe, or Cr and at least one additional metal selected from Ni, V, Cu, Mn, Co or Fe.
In some embodiments of formula II, A is A11−zA2z, where A1 is selected from Ca, Sr, Ba, Mg, Sc, Y, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof, A2 is selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or any combination thereof, and z is from 0 to less than 1.
In any of the above embodiments, if Ma is Mn and Mb is Mg then x+y may be less than 1, such as less than or equal to 0.95 or less than or equal to 0.9, or x+y may be greater than 1, such as greater than or equal to 1.05 or greater than or equal to 1.1.
In some embodiments Ma comprises Ni, Co or any combination thereof, and in other embodiments, Mb comprises Ti. In particular embodiments A is Ca, La, Sr or any combination thereof. In some examples, x is from 0.01 to 2 and/or y is from 0 to 2 or from 0.01 to 2, and in certain examples, x+y is less than or equal to 4. Compounds having formula II may also have a hibonite crystal structure.
In some particular embodiments of formula II, Ma is Co or Ni. In some particular examples, Mb is selected from Ti, Ge, Sn or any combination thereof, and/or x is from 0.05 to 1.5.
In some embodiments, the compounds are chromophoric, i.e. they absorb certain wavelengths of visible light and transmit or reflect other wavelengths, and in certain embodiments they have a blue color. The blue color may have a wavelength of from about 440 nm to about 510 nm, typically from about 450 nm to about 475 nm. In any of the above embodiments, the compound may be a synthesized blue hibonite compound.
Also disclosed are embodiments of a composition comprising a disclosed compound and at least one additional component. The composition may be, for example, a paint, an ink, a dye, a glass, a plastic, an emulsion, a fabric, or a cosmetic preparation. Examples of additional composition components include, without limitation, a binder, a solvent, a catalyst, a thickener, a stabilizer, an emulsifier, a texturizer, an adhesion promoter, a UV stabilizer, a flattener, a preservative, a polymer, a dispersion aid, a plasticizer, a flame retardant, an oxide of a metal, or any combination thereof. In some embodiments where the composition is a glass, the additional component is an oxide of a metal, including, but not limited to, oxides of silicon, boron, germanium or any combination thereof. In some embodiments, the composition has a blue color, and in certain embodiments the blue color has a wavelength of from about 440 nm to about 510 nm, preferably from about 450 nm to about 475 nm. Optionally, the composition may comprise at least one additional compound disclosed herein, and this additional compound may have formula I.
Also disclosed are embodiments of a method for making disclosed compounds and compositions. One disclosed embodiment comprises selecting the metals desired in the compound, providing reactants comprising the desired metals, and combining the reactants in stoichiometric amounts to achieve a desired final ratio of the metals in the compound. The combination of reactants is then heated at an effective temperature and for an effective period of time to make the desired compound. In certain embodiments, the effective temperature is from about 1,200° C. to about 1,500° C., and the time is from greater than zero hours to about 48hours.
In certain embodiments, the reactants comprise metal carbonates, metal oxides, metal nitrates, metal hydroxides or combinations thereof. In some embodiments the reactants are provided in a powdered form, and optionally may be pressed into a pellet before heating. The method may further comprise grinding the pellet after heating to produce a powder, pressing the powder into a pellet, and heating the pellet at a temperature of from about 1,300° C. to about 1,500° C. for from greater than zero hours to about 48 hours.
Embodiments of a method for making disclosed compositions comprise providing the compound and combining it with at least one additional component to make the composition.
Also disclosed are embodiments of a method of varying the color in a compound with formula II. In certain embodiments, the method comprises selecting metals A, Ma and Mb and the values of x and y to provide a desired color. Reactants are then selected comprising the desired metals, and are combined in stoichiometric amounts according to the values of x and y. The combination of reactants is heated at an effective temperature for an effective period of time to make the desired compound with the desired color.
Additionally, disclosed are embodiments of a method of using a disclosed compound, comprising providing a composition comprising the compound and applying the composition to a surface.
The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.



BRIEF DESCRIPTION OF THE DRAWINGS
The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
FIG. 1 provides a representation of the crystal structure of hexagonal CaAl12O19 with a hibonite structure, with Ca atoms in dark gray; oxygen atoms in red; AlO6 octahedra in cyan, yellow and pink; AlO5 trigonal bipyramids in dark blue; and AlO4 tetrahedra in green.
FIG. 2 provides a comparison of XRD patterns and pellet colors illustrating the difference between the pure nickel-doped hibonite phase (CaAl10TiNiO19 as an example) disclosed herein and the nickel-containing CaAl12O19 mixed phase made according to the method disclosed by Costa et al.
FIG. 3 provides a series of color photographs of blue pellets and powders of CaAl12−2xTixNixO19 (x=0-1.2) demonstrating that color can be selected by the appropriate selection of metals and their relative amounts.
FIG. 4 provides a series of color photographs illustrating various colors of exemplary compounds with hibonite structure, having the formulae CaAl12−x−yMxNiyO19 (M=Ti, Sn, Ge, Sb, Nb; x,y=0.2-0.5).
FIG. 5 provides a series of X-ray powder diffraction patterns for CaAl12−2xTixNixO19 (x=0-1.2) solid solutions.
FIG. 6 provides the results of cell edge calculations by whole pattern fitting for CaAl11Sn0.5Ni0.5O19.
FIG. 7 provides unit cell dimensions in angstroms (Å) for cell edges ‘a’ and ‘c’ for solid solutions of CaAl12−2xTixNixO19 (x=0-1.2), illustrating that as the composition changes, the dimensions of the crystal vary correspondingly.
FIG. 8 provides unit cell volumes in cubic angstroms (Å3) for solid solutions of CaAl12−2xTixNixO19 (x=0-1.2), illustrating that the unit cell volume varies correspondingly with the changes to the composition.
FIG. 9 provides a series of diffuse reflectance spectra for CaAl12−2xTixNixO19 (x=0-1.2) solid solutions, indicating that as x increases absorbance of light with wavelengths in the blue region of the spectrum remains low, but absorbance in other regions of the spectrum increases, resulting in blue colored compounds.



DETAILED DESCRIPTION
I. Compounds
A. Overview
The mineral known as hibonite has the ideal formula CaAl12O19. It rarely occurs naturally on Earth but has been observed frequently in meteors. As with most minerals, small amounts of other elements are found in hibonite samples. The other elements that have been reported in hibonite mineral samples are Ti, V, Cr, Mg, Si, La, Ce, Y, Sc and Th. The amounts of these trace elements are usually less than 1% and always less than 4%. It is notable that none of the many mineral samples analyzed contained detectable amounts of Ni, Cu, Zn, Ga, or In. The detection limit of these analyses is such that any amount exceeding about 0.01% would be found. Thus the compounds disclosed herein are very different than any observed in mineral samples of hibonite.
Although the color of pure CaAl12O19 hibonite is white, mineral samples are normally colored due to trace elements or defects. Observed colors are grey, dark brown, orange and blue. Attempts to correlate color with trace elements or defects have not led to a consensus.
The color of crystals is often very different from that of the powder obtained by grinding the crystals. For example, crystals of CoAl2O4 are black, but powder of the same composition and structure is a bright blue. Bright blue sapphire crystals yield a pale blue powder when ground up. Thus, it might be expected that grinding up blue hibonite crystals would produce a pale blue powder that would be of little commercial interest as a pigment.
Pure CaAl12O19 is white with a structure generally described in space group P63/mmc with unit cell dimensions of a=b=5.5587 Å, c=21.8929 Å, α=β=90°, γ=120°. This hexagonal crystal structure can be viewed as two-dimensional sections perpendicular to the c axis with alternating “spinel blocks” and trigonal bipyramidal blocks (FIG. 1). Without being bound by any particular theory, it currently is believed that there are five different coordination sites for Al, including three distinct octahedra, one tetrahedron, and an unusual trigonal bipyramid connected as a corner-sharing, edge-sharing or face-sharing polyhedral network. The cation in the trigonal bipyramid polyhedron is usually displaced from the center.
The Subramanian group at Oregon State University recently discovered that a surprisingly intense bright-blue color can be obtained when Mn3+ is introduced into the trigonal bipyramidal sites of hexagonal YInP3. A range of blue colors can be obtained over much of the YIn1−xMnxO3 solid-solution by substituting Mn for In. Similar blue color is obtained when Mn3+is introduced into trigonal bipyramidal sites in other layered oxides. The resulting blue color is a consequence of both the crystal field splitting associated with the trigonal bipyramidal coordination and the short apical Mn—O bonds.
Costa et al. reported so-called Ni-doped hibonite as a new turquoise blue ceramic pigment, the color of which, however, is in fact only turquoise (G. Costa, et al. Journal of the European Ceramic Society 29 (2009) 2671-2678). Costa et al. provide no structural analysis, and the X-ray diffraction patterns displayed SnO2 as the major phase with very small amount of hibonite in the mixture. FIG. 2 provides a comparison of the XRD patterns and pellet colors of the pure nickel-doped hibonite phase of CaAl10TiNiO19, as disclosed herein, and the nickel-containing CaAl12O19 mixed phase made according to the procedure disclosed by Costa et al. The top line of FIG. 2 shows an XRD pattern illustrating single phase CaAl10TiNiO19 hibonite as described herein, with a deep sky blue pellet color. The middle lines in FIG. 2 provide calculated XRD patterns for hibonite CaAl12O19 and cassiterite SnO2. And the bottom line in FIG. 2 provides the XRD pattern taken from the paper by Costa et al. indicating a mixed phase with a light turquoise color: A—anorthite; C—cassiterite; H—hibonite.
Given the very small amount of hibonite detected, and the fact that SnO2 is grayish white and NiAl2O4 is dark turquoise, the color of the Costa et al. material is most likely not from a hibonite phase.
B. Compounds
Disclosed herein are compounds, typically having a hibonite structure, and in certain embodiments the disclosed compounds are colored compounds. In some embodiments, the compounds have a space group P63/mmc.
The disclosed hibonite compounds typically have a general formula I

AM12O19  I

where A is selected from an alkali metal, an alkaline earth metal, a rare earth metal, Pb, Bi or any combination thereof; and M is selected from Al, Ni, Ti, V, Cr, Mn, Fe, Co, Cu, Zn Ga, Ge, Si, In, Sn, Mg, Zr, Hf, Nb, Ta, Sb, Te, Mo, W or combinations thereof. In other embodiments, A is selected from Ca, Sr, Ba, Mg, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof. In some embodiments, M comprises Al, one or more metals selected from Ni, Cr, Cu, V, Mn, Fe, or Co, and optionally one or more metals selected from Ti, Sn, Ge, Si, Zr, Hf, Ga, In, Zn, Mg, Nb, Ta, Sb, Mo, W or Te.

Also disclosed herein are compounds having a general formula II

AAl12−x−yMaxMbyO19  II.

With reference to formula II, A is selected from an alkali metal, alkaline earth metal, rare earth metal, Pb, Bi or any combination thereof; Ma is selected from Ni, Fe, Cu, Cr, V, Mn, or Co or any combination thereof; Mb is selected from Ti, Sn, Ge, Si, Zr, Hf, Ga, In, Zn, Mg, Nb, Ta, Sb, Mo, W or Te or any combination thereof. Typically, A is selected from Ca, Sr, Ba, Mg, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof. In some embodiments, x is from 0.01 to less than 12, y is from 0 to less than 12, x+y is less than 12, and if y is 0 then x is from 0.01 to less than 1. In other embodiments, x is from 0.01 to less than 1, y is from 0 to less than 12, and x+y is less than 12. In certain embodiments, x is from 0.01 to less than 12, y is from 0.01 to less than 12, and x+y is less than 12.

In some examples, A is A11−zA2z, and A1 is selected from Ca, Sr, Ba, Mg, Sc, Y, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof; A2 is selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or any combination thereof; and z is from 0 to less than 1, such as from 0 to 0.98, 0 to 0.95, or 0 to 0.9.
In some embodiments, Ma comprises Fe and y is greater than 0, such as greater than or equal to 0.01 or greater than or equal to 0.1, and in some other embodiments, Ma comprises Fe and at least one additional metal selected from Ni, Cu, Cr, V, Mn, or Co. In other embodiments, Ma is selected from Ni, Cu, Cr, V, Mn, or Co or any combination thereof.
In any of the above embodiments, if Ma is Mn and Mb is Mg, then x+y may be less than 1, such as less than or equal to 0.95 or less than or equal to 0.9, or x+y may be greater than 1,such as greater than or equal to 1.05 or greater than or equal to 1.1.
In some embodiments, y is from greater than 0 to less than 12, such as from 0.01 to less than 12, or from 0.1 to less than 12. In other embodiments, Ma comprises at least two metals selected from Ni, Cr, Cu, V, Mn, Co, Fe. In some examples, Ma comprises V and at least one additional metal selected from Ni, Cu, Cr, Fe, Mn, or Co. In other examples, Ma comprises Cr and at least one additional metal selected from Ni, Cu, Fe, V, Mn, or Co.
In some examples, x+y is less or equal to 4, and in other examples, x is from about 0.01to about 2, and/or y is from 0 to about 2 or y is from about 0.01 to about 2.
While not being bound to any particular theory, is it believed that Ma cations are chromophores, i.e. they are the part of the compound that is responsible for the color, and that Mb cations can be used to enhance the color and/or for charge balance.
In certain embodiments, Ma comprises Ni, La, Co or any combination thereof. In some particular embodiments of formula II, Ma is Co or Ni. In some embodiments, x is from 0.05 to 1.5 and/or Mb is selected from Ti, Ge, Sn or any combination thereof.
In some working embodiments, exemplary compounds were prepared where Ma comprised Ni or Co. Other compounds were prepared such that Mb comprised Ti. In certain working embodiments, A comprised Ca, Sr, La, Ce, Pr, Nd, Y, Sc, K, Na, Rb, Mg, Ba, Yb or combinations thereof. In some working embodiments, A was Ca and Sr, Sr and La, Ca and La, Ca and Y, Ca and Ce, Ca and Pr, Ca and Na, Ca and K, Ca and Rb, Ca and Cs, Ca and Mg, Ca and Ba, Sr and Y, Sr and Ce, Sr and Nd, Sr and Pr, Ca and Sc, Ca and Yb, or Ca and Nd. In other working embodiments, A was Ca, Sr, Ce, La, Pr or Nd, and in particular working embodiments A comprised Ca, La, Sr or any combination thereof.
Exemplary compounds according to the present invention are selected from CaAl11.8Ni0.2O19, CaAl11.5Ni0.5O19, CaAl11Sn0.5Ni0.5O19, CaAl10SnNiO19, CaAl11Zn0.5Ni0.5O19, CaAl11Ge0.5Ni0.5O19, CaAl10GeNiO19, CaAl11Ga0.5Ni0.5O19, CaAl11Ti0.5Ni0.5O19, CaAl10Ti0.5Si0.5NiO19, CaAl10Ti0.5Ge0.5NiO19, CaAl10Ti0.5Sn0.5NiO19, CaAl8TiSnNi2O19, CaAl10TiNi0.5Cu0.5O19, CaAl10TiNi0.5Cr0.5O19, CaAl10TiNi0.5Zn0.5O19, CaAl11.8Ti0.1Ni0.1O19, CaAl11.6Ti0.2Ni0.2O19, CaAl11.4Ti0.3Ni0.3O19, CaAl11.2Ti0.4Ni0.4O19, CaAl11Ti0.5Ni0.5O19, CaAl10.8Ti0.6Ni0.6O19, CaAl10.6Ti0.7Ni0.7O19, CaAl10.4Ti0.8Ni0.8O19, CaAl10.2Ti0.9Ni0.9O19, CaAl10TiNiO19, CaAl9.6Ti1.2Ni1.2O19, CaAl8Ti2Ni2O19, Ca0.8Sr0.2Al11.6Ti0.2Ni0.2O19, Ca0.6Sr0.4Al11.2Ti0.4Ni0.4O19, Ca0.4Sr0.6Al10.8Ti0.6Ni0.6O19, Ca0.2Sr0.8Al10.4Ti0.8Ni0.8O19, SrAl10TiNiO19, SrAl9.6Ti1.2Ni1.2O19, SrAl11Ti0.5Ni0.5O19, SrAl8Ti2Ni2O19, Ca0.5Sr0.5Al8Ti2Ni2O19, Ca0.5Sr0.5Al10TiNiO19, Ca0.5Sr0.5Al10GeNiO19, Ca0.5Sr0.5Al11Sn0.5Ni0.5O19, Ca0.5Sr0.5Al10SnNiO19, Sr0.9La0.1Al11.9Ni0.1O19, Sr0.8La0.2Al11.8Ni0.2O19, Sr0.7La0.3Al11.7Ni0.3O19, Sr0.6La0.4Al11.6Ni0.4O19, Sr0.5La0.5Al11.5Ni0.5O19, Sr0.4La0.6Al11.4Ni0.6O19, Sr0.3La0.7Al11.3Ni0.7O19, Sr0.2La0.8Al11.2Ni0.8O19, Sr0.1La0.9Al11.1Ni0.9O19, Ca0.9La0.1Al11.9Ni0.1O19, Ca0.8La0.2Al11.8Ni0.2O19, Ca0.7La0.3Al11.7Ni0.3O19, Ca0.6La0.4Al11.6Ni0.4O19, Ca0.5La0.5Al11.5Ni0.5O19, Ca0.4La0.6Al11.4Ni0.6O19, Ca0.3La0.7Al11.3Ni0.7O19, Ca0.2La0.8Al11.2Ni0.8O19, Ca0.1La0.9Al11.1Ni0.9O19, LaAl11NiO19, Ca0.75La0.25Al11.25Ti0.25Ni0.5O19, Ca0.5La0.5Al11Ti0.25Ni0.75O19, Ca0.5La0.5Al10.5Ti0.5NiO19, Ca0.25La0.75Al9.75Ti0.75Ni1.5O19, Ca0.5La0.5Al8.5Ti1.5Ni2019, LaAl9TiNi2O19, Ca0.5La0.5Al11In0.5Ni0.5O19, Ca0.5La0.5Al11Ga0.5Ni0.5O19, Ca0.5La0.5Al11Ge0.25Ni0.75O19, Ca0.5La0.5Al11Sn0.25Ni0.75O19, Ca0.75La0.25Al11.75Ni0.25O19, Ca0.5Y0.5Al11Ti0.25Ni0.75O19, Ca0.5Ce0.5Al11Ti0.25Ni0.75O19, Ca0.5Pr0.5Al11Ti0.25Ni0.75O19, Ca0.5Na0.5Al10.5TiNi0.5O19, Ca0.5K0.5Al10.5TiNi0.5O19, Ca0.5Rb0.5Al10.5TiNi0.5O19, Ca0.5Cs0.5Al10.5TiNi0.5O19, Ca0.8Mg0.2Al11.6Ti0.2Ni0.2O19, Ca0.5Ba0.5Al8Ti2Ni2O19, Sr0.9Y0.1Al11.9Ni0.1O19, Sr0.8Y0.2Al11.8Ni0.2O19, Sr0.8Ce0.2Al11.8Ni0.2O19, Sr0.8Nd0.2Al11.8Ni0.2O19, Sr0.8Pr0.2Al11.8Ni0.2O19, Ca0.9Y0.1Al11.9Ni0.1O19, Ca0.8Y0.2Al11.8Ni0.2O19, Ca0.7Y0.3Al11.7Ni0.3O19, Ca0.6Y0.4Al11.6Ni0.4O19, Ca0.5La0.5Al10.5Zn0.5Sn0.5Ni0.5O19, Ca0.5La0.5Al10.5Cu0.5Sn0.5Ni0.5O19, Ca0.8Sc0.2Al11.8Ni0.2O19, Ca0.8Yb0.2Al11.8Ni0.2O19, Ca0.7Sr0.3Al11.5Ni0.5O19, CaAl7Ti1.5Ge0.5MgNi2O19, Ca0.9Ce0.1Al11.9Ni0.1O19, Ca0.8Ce0.2Al11.8Ni0.2O19, Ca0.7Ce0.3Al11.7Ni0.3O19, Ca0.6Ce0.4Al11.6Ni0.4O19, Ca0.5Ce0.5Al11.5Ni0.5O19, Ca0.4Ce0.6Al11.4Ni0.6O19, Ca0.3Ce0.7Al11.3Ni0.7O19, Ca0.2Ce0.8Al11.2Ni0.8O19, Ca0.1Ce0.9Al11.1Ni0.9O19, CeAl11NiO19, Ca0.9Pr0.1Al11.9Ni0.1O19, Ca0.8Pr0.2Al11.8Ni0.2O19, Ca0.7Pr0.3Al11.7Ni0.3O19, Ca0.6Pr0.4Al11.6Ni0.4O19, Ca0.5Pr0.5Al11.5Ni0.5O19, Ca0.4Pr0.6Al11.4Ni0.6O19, Ca0.3Pr0.7Al11.3Ni0.7O19, Ca0.2Pr0.8Al11.2Ni0.8O19, Ca0.1Pr0.9Al11.1Ni0.9O19, PrAl11NiO19, Ca0.9Nd0.1Al11.9Ni0.1O19, Ca0.8Nd0.2Al11.8Ni0.2O19, Ca0.7Nd0.3Al11.7Ni0.3O19, Ca0.6Nd0.4Al11.6Ni0.4O19, Ca0.5Nd0.5Al11.5Ni0.5O19, Ca0.4Nd0.6Al11.4Ni0.6O19, Ca0.3Nd0.7Al11.3Ni0.7O19, Ca0.2Nd0.8Al11.2Ni0.8O19, Ca0.1Nd0.9Al11.1Ni0.9O19, NdAl11NiO19, CaAl11.4Nb0.2Ni0.4O19, CaAl11.4Ta0.2Ni0.4O19, CaAl11.4V0.2Ni0.4O19, CaAl11.4Sb0.2Ni0.4O19, CaAl11Zr0.5Ni0.5O19 or CaAl11Te0.5Ni0.5O19.
In any of the above embodiments the compounds may have a hibonite crystal structure, and in any of the above embodiments the compounds may be chromophoric. In some embodiments, the compounds are blue. In particular embodiments, disclosed compounds have a blue color with a wavelength of from about 440 nm to about 510 nm, preferably from about 450 nm to about 475 nm. In certain working embodiments, compounds where Ma comprised Ni had a blue color.
II. Method of Making Compounds
A general method for making the compounds disclosed herein comprises providing a mixture of reactants selected to produce a desired compound and heating the reactants.
The compounds can be made in different forms, such as powders and pellets. To make pellets of the disclosed compounds, the metals desired in the final compounds are selected. Reactants are then combined in stoichiometric amounts to achieve the desired final ratio of the metals in the compound. Reactants suitable to make the disclosed compounds include elemental metals, and compounds that comprise the desired metals, including, but not limited to, oxides, carbonates, nitrates, nitrites, nitrides, azides, sulfates, sulfites, halides such as chloride, bromide, iodide or fluoride, phosphates, hydroxides, hydrates, or any combination thereof. In some embodiments, the reactants are either metal oxides, or compounds that decompose to provide metal oxides. In working embodiments, the alkali metals and alkaline earth metals were typically provided as metal carbonate salts, and the other metals were typically provided as metal oxides. In some embodiments, the reactants are ground to a powder, either before, during or after mixing, and optionally formed into a pellet.
The combination of reactants is then heated at an effective temperature for an effective period of time to form the desired compound. In some embodiments, the temperature is from about 800° C. to about 2,000° C., typically from about 1,100° C. to about 1,700° C., and even more typically from about 1,200° C. to about 1,500° C. The effective period of time is from greater than zero hours up to at least 72 hours, typically from about 4 hours to about 60 hours, and more typically from about 10 hours to about 48 hours. In some embodiments, reactants are heated at an effective temperature in the presence of air. A person of ordinary skill in the art will appreciate that, if atmospheric oxygen is not required to produce desired compounds, reactants can be heated in an inert atmosphere. A person of ordinary skill in the art also will appreciate that a pressure effective to produce the desired compounds could be about atmospheric pressure or less than atmospheric pressure, such as from less than 1 mm Hg to about 760 mmHg, preferably from about 10 mm Hg to about 700 mm Hg. Or the pressure could be greater than atmospheric pressure, such as from about 1 atmosphere pressure to greater than 10 atmospheres, preferably from about 1.1 atmospheres to about 5 atmospheres pressure.
After heating, the compounds are characterized by X-ray diffraction. If the X-ray diffraction indicates that the compound is impure, i.e. it is not a single phase, the compound is ground into a powder, re-pelletized and reheated. The reheating temperature could be substantially the same as the initial heating temperature, or it could be higher or lower than the initial heating temperature. The pellet is typically reheated for from about 2 to about 48 hours. The grinding, re-pelletizing and reheating is repeated until the X-ray diffraction indicates a pure compound, i.e. a single phase. In certain working embodiments, the combination of reactants was heated at about 1,300° C. for about 12 hours, then ground to a powder, re-pelletized and reheated at from about 1,300° C. to about 1,500° C. for about 12 hours. To make powders of the disclosed compound, the pellets are ground after the final heating step.
Exemplary compounds made according to the disclosed method are characterized by X-ray diffraction, diffuse reflectance spectroscopy and magnetic susceptibility. Table 1, below, lists exemplary compounds and information regarding their color, starting materials and reaction conditions.







TABLE 1







Composition, color and structures of exemplary compounds













Heating





Temperatures


Composition
Color
Starting Materials
and Times





CaAl12O19
white
CaCO3, Al2O3
1st: 1300° C., 12 hr;





2nd: 1500° C., 12 hr


CaAl11.8Mn0.2O19
tan/burlywood
CaCO3, Al2O3, Mn2O3
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.5Mn0.5O19
gray
CaCO3, Al2O3, Mn2O3
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.8Ni0.2O19
pale turquoise
CaCO3, Al2O3, NiO
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.5Ni0.5O19
light sky blue
CaCO3, Al2O3, NiO
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.8Co0.2O19
light purplish
CaCO3, Al2O3, Co3O4
1st: 1300° C., 12 hr;



blue

2nd: 1450° C., 12 hr


CaAl11.8Ti0.2O19
white
CaCO3, Al2O3, TiO2
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.8Cr0.2O19
light pink
CaCO3, Al2O3, Cr2O3
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.8V0.2O19
mint cream
CaCO3, Al2O3, V2O5
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11.8Cu0.2O19
misty rose
CaCO3, Al2O3, CuO
1st: 1300° C., 12 hr;





2nd: 1450° C., 12 hr


CaAl11Sn0.5Mn0.5O19
light pink
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;




Mn2O3
2nd: 1450° C., 12 hr


CaAl11Sn0.5Ni0.5O19
sky blue
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl10SnNiO19
deep sky blue
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


CaAl11Sn0.5Fe0.5O19
light greenish
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;



beige
Fe2O3
2nd: 1450° C., 12 hr


CaAl11Sn0.5Cu0.5O19
White
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;




CuO
2nd: 1450° C., 12 hr


CaAl11Sn0.5Cr0.5O19
light pink
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;




Cr2O3
2nd: 1450° C., 12 hr


CaAl11Zn0.5Ni0.5O19
light blue
CaCO3, Al2O3, ZnO, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11Ge0.5Ni0.5O19
sky blue
CaCO3, Al2O3, GeO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl10GeNiO19
deep sky blue
CaCO3, Al2O3, GeO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


CaAl11Ga0.5Ni0.5O19
light turquoise
CaCO3, Al2O3, 
1st: 1300° C., 12 hr;




Ga2O3, NiO
2nd: 1450° C., 12 hr


CaAl11Ti0.5Ni0.5O19
deep sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11Ti0.5Cu0.5O19
ivory
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




CuO
2nd: 1450° C., 12 hr


CaAl11Ti0.5Fe0.5O19
light dark khaki
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




Fe2O3
2nd: 1450° C., 12 hr


CaAl11Ti0.5Mn0.5O19
very light pink
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




Mn2O3
2nd: 1450° C., 12 hr


CaAl10Ti0.5Si0.5NiO19
sky blue
CaCO3, Al2O3, 
1st: 1300° C., 12 hr;




TiO2, SiO2, NiO
2nd: 1450° C., 12 hr


CaAl10Ti0.5Ge0.5NiO19
royal blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




GeO2, NiO
2nd: 1450° C., 12 hr


CaAl10Ti0.5Sn0.5NiO19
deep sky blue
CaCO3, Al2O3, 
1st: 1300° C., 12 hr;




TiO2, SnO2, NiO
2nd: 1450° C., 12 hr


CaAl8TiSnNi2O19
dark 
CaCO3, Al2O3, 
1st: 1300° C., 12 hr;



turquoise/cyan
TiO2, SnO2, NiO
2nd: 1350° C., 12 hr


CaAl10TiNi0.5Cu0.5O19
dark slate gray
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




CuO, NiO
2nd: 1450° C., 12 hr


CaAl10TiNi0.5Cr0.5O19
dark turquoise
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




Cr2O3
2nd: 1450° C., 12 hr


CaAl10TiNi0.5Zn0.5O19
deep sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




CuO, NiO
2nd: 1450° C., 12 hr


CaAl11.8Ti0.1Ni0.1O19
light sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11.6Ti0.2Ni0.2O19
sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11.4Ti0.3Ni0.3O19
sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11.2Ti0.4Ni0.4O19
deep sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


CaAl11Ti0.5Ni0.5O19
deep sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


CaAl10.8Ti0.6Ni0.6O19
dark sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1350° C., 12 hr


CaAl10.6Ti0.7Ni0.7O19
dodger blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1350° C., 12 hr


CaAl10.4Ti0.8Ni0.8O19
dodger blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


CaAl10.2Ti0.9Ni0.9O19
dodger blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


CaAl10TiNiO19
deep sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


CaAl9.6Ti1.2Ni1.2O19
royal blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


CaAl8Ti2Ni2O19
dark sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


CaAl11Ge0.5Mn0.5O19
light salmon
CaCO3, Al2O3, GeO2, 
1st: 1300° C., 12 hr;




MnO
2nd: 1400° C., 12 hr


CaAl11In0.5Mn0.5O19
saddle brown
CaCO3, 
1st: 1300° C., 12 hr;




Al2O3, In2O3, Mn2O3
2nd: 1400° C., 12 hr


CaAl11Sn0.5Mn0.5O19
light pink
CaCO3, Al2O3, SnO2, 
1st: 1300° C., 12 hr;




MnO
2nd: 1400° C., 12 hr


CaAl11Ti0.5Mn0.5O19
tan
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




MnO
2nd: 1400° C., 12 hr


Ca0.8Sr0.2Al11.6Ti0.2Ni0.2O19
light sky blue
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.6Sr0.4Al11.2Ti0.4Ni0.4O19
sky blue
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.4Sr0.6Al10.8Ti0.6Ni0.6O19
darker sky blue
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.2Sr0.8Al10.4Ti0.6Ni0.8O19
darker sky blue
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


SrAl10TiNiO19
deep sky blue
SrCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


SrAl9.6Ti1.2Ni1.2O19
deep sky blue
SrCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


SrAl11Ti0.5Ni0.5O19
light blue
SrCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


SrAl8Ti2Ni2O19
dark 
SrCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;



turquoise/cyan
NiO
2nd: 1300° C., 12 hr


Ca0.5Sr0.5Al8Ti2Ni2O19
dark turquoise
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1300° C., 12 hr


Ca0.5Sr0.5Al10TiNiO19
dodger blue
CaCO, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1300° C., 12 hr


Ca0.5Sr0.5Al10GeNiO19
deep sky blue
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, GeO2, NiO
2nd: 1300° C., 12 hr


Ca0.5Sr0.5Al11Sn0.5Ni0.5O19
sky blue 
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;



(bright)
Al2O3, SnO2, NiO
2nd: 1400° C., 12 hr


Ca0.5Sr0.5Al10SnNiO19
deep sky blue
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, SnO2, NiO
2nd: 1300° C., 12 hr


Sr0.9La0.1Al11.9Ni0.1O19
Light Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.8La0.2Al11.8Ni0.2O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.7La0.3Al11.7Ni0.3O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.6La0.4Al11.6Ni0.4O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.5La0.5Al11.5Ni0.5O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


Sr0.4La0.6Al11.4Ni0.6O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


Sr0.3La0.7Al11.3Ni0.7O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1350° C., 12 hr


Sr0.2La0.8Al11.2Ni0.8O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1350° C., 12 hr


Sr0.1La0.9Al11.1Ni0.9O19
Sky Blue
SrCO3, La2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


SrAl12O19
white
SrCO3, Al2O3
1st: 1300° C., 12 hr;





2nd: 1500° C., 12 hr


Ca0.9La0.1Al11.9Ni0.1O19
Light Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.8La0.2Al11.8Ni0.2O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.7La0.3Al11.7Ni0.3O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.6La0.4Al11.6Ni0.4O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.5La0.5Al11.5Ni0.5O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


Ca0.4La0.6Al11.4Ni0.6O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


Ca0.3La0.7Al11.3Ni0.7O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1350° C., 12 hr


Ca0.2La0.8Al11.2Ni0.8O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1350° C., 12 hr


Ca0.1La0.9Al11.1Ni0.9O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1300° C., 12 hr


LaAl11NiO19
Sky Blue
La2O3, Al2O3, NiO
1st: 1300° C., 12 hr;





2nd: 1300° C., 12 hr


Ca0.75La0.25Al11.25Ti0.25Ni0.5O19
deep sky blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.5La0.5Al11Ti0.25Ni0.75O19
deep sky blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;



(brighter)
Al2O3, TiO2, NiO
2nd: 1350° C., 12 hr


Ca0.5La0.5Al10.5Ti0.5NiO19
royal blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;



(darker)
Al2O3, TiO2, NiO
2nd: 1450° C., 12 hr


Ca0.25La0.75Al9.75Ti0.75Ni1.5O19
royal blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;



(darkest)
Al2O3, TiO2, NiO
2nd: 1300° C., 12 hr


Ca0.5La0.5Al8.5Ti1.5Ni2O19
dark turquoise
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1300° C., 12 hr


LaAl9TiNi2O19
dark turquoise
La2O3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


Ca0.5La0.5Al11In0.5Ni0.5O19
light cyan
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, In2O3, NiO
2nd: 1400° C., 12 hr


Ca0.5La0.5Al11Ga0.5Ni0.5O19
light cyan
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, Ga2O3, NiO
2nd: 1400° C., 12 hr


Ca0.5La0.5Al11Ge0.25Ni0.75O19
deep sky blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, GeO2, NiO
2nd: 1350° C., 12 hr


Ca0.5La0.5Al11Sn0.25Ni0.75O19
deep sky blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, SnO2, NiO
2nd: 1350° C., 12 hr


Ca0.75La0.25Al11.75Ni0.25O19
Sky Blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.5Y0.5Al11Ti0.25Ni0.75O19
turquoise
CaCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




TiO2, NiO
2nd: 1350° C., 12 hr


Ca0.5Ce0.5Al11Ti0.25Ni0.75O19
deep sky blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




TiO2, NiO
2nd: 1350° C., 12 hr


Ca0.5Pr0.5Al11Ti0.25Ni0.75O19
deep sky blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1350° C., 12 hr


Ca0.5Na0.5Al10.5TiNi0.5O19
bright royal 
CaCO3, Na2CO3, 
1st: 1300° C., 12 hr;



blue
Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.5K0.5Al10.5TiNi0.5O19
deep sky blue
CaCO3, K2CO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.5Rb0.5Al10.5TiNi0.5O19
royal blue
CaCO3, Rb2CO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.5Cs0.5Al10.5TiNi0.5O19
deep sky blue
CaCO3, Cs2CO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1400° C., 12 hr


Ca0.8Mg0.2Al11.6Ti0.2Ni0.2O19
light sky blue
CaCO3, MgO, Al2O3, 
1st: 1300° C., 12 hr;




TiO2, NiO
2nd: 1450° C., 12 hr


Ca0.5Ba0.5Al8Ti2Ni2O19
dark turquoise
CaCO3, BaCO3, 
1st: 1300° C., 12 hr;




Al2O3, TiO2, NiO
2nd: 1300° C., 12 hr


Sr0.9Y0.1Al11.9Ni0.1O19
light sky blue
SrCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.8Y0.2Al11.8Ni0.2O19
sky blue
SrCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.8Ce0.2Al11.8Ni0.2O19
sky blue
SrCO3, CeO4, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.8Nd0.2Al11.8Ni0.2O19
sky blue
SrCO3, Nd2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Sr0.8Pr0.2Al11.8Ni0.2O19
sky blue
SrCO3, Pr6O11, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.9Y0.1Al11.9Ni0.1O19
Light Sky Blue
CaCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.8Y0.2Al11.8Ni0.2O19
Sky Blue
CaCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.7Y0.3Al11.7Ni0.3O19
Sky Blue
CaCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.6Y0.4Al11.6Ni0.4O19
Sky Blue
CaCO3, Y2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


Ca0.5La0.5Al10.5Zn0.5Sn0.5Ni0.5O19
Dark bluish
CaCO3, La2O3, 
1st: 1300° C., 12 hr;



turquoise
Al2O3, ZnO, SnO2, 
2nd: 1400° C., 12 hr




NiO



Ca0.5La0.5Al10.5Cu0.5Sn0.5Ni0.5O19
deep sky blue
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, CuO, SnO2, 
2nd: 1400° C., 12 hr




NiO



Ca0.8Sc0.2Al11.8Ni0.2O19
light blue
CaCO3, Sc2O3, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.8Yb0.2Al11.8Ni0.5O19
light blue
CaCO3, Yb2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.7Sr0.3Al11.5Ni0.5O19
light turquoise
CaCO3, SrCO3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


CaAl7Ti1.5Ge0.5MgNi2O19
sky blue
CaCO3, Al2O3, TiO2, 
1st: 1300° C., 12 hr;




GeO2, MgO, NiO
2nd: 1300° C., 12 hr


Ca0.5La0.5Al11.5Mn0.5O19
saddle brown
CaCO3, La2O3, 
1st: 1300° C., 12 hr;




Al2O3, MnO
2nd: 1400° C., 12 hr


Ca0.9Ce0.1Al11.9Ni0.1O19
Light Sky
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;



Blue
NiO
2nd: 1450° C., 12 hr


Ca0.8Ce0.2Al11.8Ni0.2O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.7Ce0.3Al11.7Ni0.3O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.6Ce0.4Al11.6Ni0.4O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


Ca0.5Ce0.5Al11.5Ni0.5O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


Ca0.4Ce0.6Al11.4Ni0.6O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1400° C., 12 hr


Ca0.3Ce0.7Al11.3Ni0.7O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1350° C., 12 hr


Ca0.2Ce0.8Al11.2Ni0.8O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1350° C., 12 hr


Ca0.1Ce0.9Al11.1Ni0.9O19
Sky Blue
CaCO3, CeO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1300° C., 12 hr


CeAl11NiO19
Sky Blue
CeO2, Al2O3, NiO
1st: 1300° C., 12 hr;





2nd: 1300° C., 12 hr


Ca0.9Pr0.1Al11.9Ni0.1O19
Light Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.8Pr0.2Al11.8Ni0.2O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.7Pr0.3Al11.7Ni0.3O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.6Pr0.4Al11.6Ni0.4O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.5Pr0.5Al11.5Ni0.5O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


Ca0.4Pr0.6Al11.4Ni0.6O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


Ca0.3Pr0.7Al11.3Ni0.7O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1350° C., 12 hr


Ca0.2Pr0.8Al11.2Ni0.8O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1350° C., 12 hr


Ca0.1Pr0.9Al11.1Ni0.9O19
Sky Blue
CaCO3, Pr6O11, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1300° C., 12 hr


PrAl11NiO19
Sky Blue
Pr6O11, Al2O3, NiO
1st: 1300° C., 12 hr;





2nd: 1300° C., 12 hr


Ca0.9Nd0.1Al11.9Ni0.1O19
Light Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.8Nd0.2Al11.8Ni0.2O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.7Nd0.3Al11.7Ni0.3O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.6Nd0.4Al11.6Ni0.4O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


Ca0.5Nd0.5Al11.5Ni0.5O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


Ca0.4Nd0.6Al11.4Ni0.6O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1400° C., 12 hr


Ca0.3Nd0.7Al11.3Ni0.7O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1350° C., 12 hr


Ca0.2Nd0.8Al11.2Ni0.8O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1350° C., 12 hr


Ca0.1Nd0.9Al11.1Ni0.9O19
Sky Blue
CaCO3, Nd2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1300° C., 12 hr


NdAl11NiO19
Sky Blue
Nd2O3, Al2O3, NiO
1st: 1300° C., 12 hr;





2nd: 1300° C., 12 hr


CaAl11.4Nb0.2Ni0.4O19
Deep sky blue
CaCO3, Nb2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


CaAl11.4Ta0.2Ni0.4O19
Deep sky blue
CaCO3, Ta2O5, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


CaAl11.4V0.2Ni0.4O19
Turquoise
CaCO3, V2O5, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11.4Sb0.2Ni0.4O19
Sky blue
CaCO3, Sb2O3, 
1st: 1300° C., 12 hr;




Al2O3, NiO
2nd: 1450° C., 12 hr


CaAl11Zr0.5Ni0.5O19
Light sky blue
CaCO3, ZrO2, Al2O3, 
1st: 1300° C., 12 hr;




NiO
2nd: 1450° C., 12 hr


CaAl11Te0.5Ni0.5O19
Very light sky 
CaCO3, TeO2, Al2O3, 
1st: 1300° C., 12 hr;



blue
NiO
2nd: 1450° C., 12 hr









The colors can be varied or selected by changing the relative ratio of metals in the compound, or by changing the composition. FIG. 3 shows the results of varying the relative ratio of metals in an exemplary series of compounds, CaAl12−2xTixNixO19 (x=0-1.2). In this series, the compound when x is 0, i.e. no Ti or Ni present, has a white color. The introduction of Ti and Ni (x=0.1) results in a blue compound. As compounds with increasing amounts of Ti and Ni are synthesized, the colors of the compounds change from a light sky blue at x=0.1 (CaAl11.8Ti0.1Ni0.1O19), through a deep sky blue at x=1.0 (CaAl10TiNiO19), to a royal blue color at x=1.2 (CaAl9.6Ti1.2Ni1.2O19). Surprisingly, the color of the pellet is substantially maintained when the pellet is ground to a powder, thereby making the compound suitable for use as a pigment (FIG. 3).
FIG. 4 shows the results of varying the composition of the compounds. In the series of compounds having a formula CaAl12−x−yMxNiyO19 (x, y=0.2-0.5), where M is Ti, Sn, Ge, Sb or Nb, all the samples have a blue color. CaAl11Sn0.5Ni0.5O19 and CaAl11.4Sb0.2Ni0.4O19 have a light sky blue color, and CaAl11Ti0.5Ni0.5O19, CaAl11Ge0.5Ni0.5O19 and CaAl11.4Nb0.2Ni0.4O19 have a deep sky blue color.
III. Compositions
The present disclosure is also concerns compositions comprising at least one disclosed compound or compounds, particularly a hibonite compound, even more particularly a blue hibonite compound or a compound having formula II, and at least one additional component. Such compositions include a paint, an ink, a dye, a glass, a plastic, an emulsion, a fabric, or a cosmetic preparation. Suitable additional components for use in paint, ink dye or emulsion products include, but are not limited to, binders, solvents, and additives such as catalysts, thickeners, stabilizers, emulsifiers, texturizers, adhesion promoters, UV stabilizers, flatteners (i.e., de-glossing agents), preservatives, and other additives known to those of ordinary skill in the art.
Suitable additional materials for use in glass products include, for example, network formers (e.g., oxides of silicon, boron, germanium) to form a highly crosslinked network of chemical bonds, modifiers (e.g., calcium, lead, lithium, sodium, potassium) that alter the network structure, intermediates (e.g., titanium, aluminum, zirconium, beryllium, magnesium, zinc) that can act as both network formers and modifiers, and combinations thereof.
Suitable additional materials for use in plastic products include, for example, dispersion aids (e.g., zinc stearate, calcium stearate, ethylene bis-steamide), plasticizers, flame retardants, internal mold release agents, slip agents, and combinations thereof.
When coloring a ceramic product, the material typically is added to a ceramic glaze composition. Other materials used in glazes include, for example, silica, metal oxides (e.g., sodium, potassium, calcium), alumina, opacifiers (e.g., tin oxide, zirconium oxide), and combinations thereof.
IV. Working Examples
The compounds disclosed herein were prepared via traditional solid state reactions.
Amounts of metal carbonates and/or metal oxides were selected and weighed to provide the desired stoichiometric amounts of the metals. Typically, the alkali metals and alkaline earth metals were provided as metal carbonate salts, and the other metals were provided as metal oxides. The starting materials were then mixed, ground and pelletized, then heated in air at a range of from about 1,200° C. to about 1,500° C. several times with intermediate grinding. Ramp rates were about 300° C./hour. Table 1, above, gives the starting metal salts and oxides for each exemplary compound, and the heating temperatures and times for each heating cycle. For example, CaCO3 (0.0721 grams, 1 molar equivalent), Al2O3 (0.4039 grams, 5.5 molar equivalents), TiO2 (0.0288 grams, 0.5 molar equivalents) and NiO (0.0269 grams, 0.5 molar equivalents) were weighed, mixed/ground, pelletized and heated in air at 1,300° C. for 12 hours, then ground to a powder, re-pelletized and reheated at 1,400° C. for 12 hours to prepare 0.5g of CaAl11Ti0.5Ni0.5O19.
X-ray diffraction patterns of exemplary solid solutions of CaAl12−2xTixNixO19 (x=0.1-1.2) are shown in FIG. 5. The X-ray diffraction data was obtained using a Rigaku Miniflex X-ray diffractometer using Cu Kα radiation and a graphite monochromator. The lattice parameters of the unit cells were calculated by whole pattern fitting as shown in FIG. 6, using the data of CaAl11Sn0.5Ni0.5O19 as an example. The results indicate that cell edge ‘a’ was 5.6075 Å, ‘c’ was 22.205 Å and the cell volume was 604.69 Å3. In comparison, for CaAl12O19 cell edge ‘a’ was 5.5636 Å, ‘c’ was 21.945 Å and the cell volume was 588.28 Å3. The increase of hibonite unit cell volume was consistent with the substitution of small Al3+ ions with larger Ni2+, Ti4+ and La3+ ions (FIGS. 7 and 8).
Diffuse reflectance spectra of powdered samples were obtained in the region 300-1100nm using a Xe lamp and a grating double monochromator as the source. The diffuse light reflected by the powders was collected with an integration sphere and detected with a Si diode detector. MgO was used as a reference. The data were transformed into absorbance using the Kubelka-Munk function.
The 400-800 nm region of diffuse reflectance spectra for solid solution of exemplary compounds CaAl12−2xTixNixO19 (x=0-1.2) are shown in FIG. 9. Strong absorption in the orange spectral region combined with relatively weak absorption in the blue region was responsible for the observed bright blue color. In pure CaAl12O19 (i.e. x=0), nearly no absorption occurs throughout the entire visible region, resulting in the white color. With increasing Ni composition, the onset of the first absorption peak shifts to lower energy and the second broadens, consistent with the gradual darkening of the samples toward royal blue.
In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims.

## Claims

1. A compound having a formula AAl12−x−yMaxMbyO19, wherein:
A is selected from Ca, Sr, Ba, Mg, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof;
Ma is selected from Ni, Fe, Cu, Cr, V, Mn, or Co or any combination thereof;
Mb is selected from Ti, Sn, Ge, Si, Zr, Hf, Ga, In, Zn, Mg, Nb, Ta, Sb, Mo, W or Te or any combination thereof;
x is from 0.01 to less than 12;
y is from 0 to less than 12;
x+y is less than 12; and
if y is 0, then x is from 0.01 to less than 1;
if Ma comprises Fe, then y is greater than 0, or Ma further comprises Ni, Cu, Cr, V, Mn, or Co or any combination thereof; and
if Ma is Mn and Mb is Mg, then x+y is less than 1, or x+y is greater than 1.

2. The compound of claim 1, wherein x is from 0.01 to less than 12 and y is from 0.01 to less than 12.

3. The compound of claim 1, wherein:
A is A11−zA2z;
A1 is selected from Ca, Sr, Ba, Mg, Sc, Y, Li, Na, K, Rb, Cs, Pb, Bi or any combination thereof;
A2 is selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or any combination thereof; and
z is from 0 to less than 1.

4. The compound of claim 1, wherein the compound is selected from CaAl11.8Ni0.2O19, CaAl11.5Ni0.5O19, CaAl11Sn0.5Ni0.5O19, CaAl10SnNiO19, CaAl11Zn0.5Ni0.5O19, CaAl11Ge0.5Ni0.5O19, CaAl10GeNiO19, CaAl11Ga0.5Ni0.5O19, CaAl11Ti0.5Ni0.5O19, CaAl10Ti0.5Si0.5NiO19, CaAl10Ti0.5Ge0.5NiO19, CaAl10Ti0.5Sn0.5NiO19, CaAl8TiSnNi2O19, CaAl10TiNi0.5Cu0.5O19, CaAl10TiNi0.5Cr0.5O19, CaAl10TiNi0.5Zn0.5O19, CaAl11.8Ti0.1Ni0.1O19, CaAl11.6Ti0.2Ni0.2O19, CaAl11.4Ti0.3Ni0.3O19, CaAl11.2Ti0.4Ni0.4O19, CaAl11Ti0.5Ni0.5O19, CaAl10.8Ti0.6Ni0.6O19, CaAl10.6Ti0.7Ni0.7O19, CaAl10.4Ti0.8Ni0.8O19, CaAl10.2Ti0.9Ni0.9O19, CaAl10TiNiO19, CaAl9.6Ti1.2Ni1.2O19, CaAl8Ti2Ni2O19, Ca0.8Sr0.2Al11.6Ti0.2Ni0.2O19, Ca0.6Sr0.4Al11.2Ti0.4Ni0.4O19, Ca0.4Sr0.6Al10.8Ti0.6Ni0.6O19, Ca0.2Sr0.8Al10.4Ti0.8Ni0.8O19, SrAl10TiNiO19, SrAl9.6Ti1.2Ni1.2O19, SrAl11Ti0.5Ni0.5O19, SrAl8Ti2Ni2O19, Ca0.5Sr0.5Al8Ti2Ni2O19, Ca0.5Sr0.5Al10TiNiO19, Ca0.5Sr0.5Al10GeNiO19, Ca0.5Sr0.5Al11Sn0.5Ni0.5O19, Ca0.5Sr0.5Al10SnNiO19, Sr0.9La0.1Al11.9Ni0.1O19, Sr0.8La0.2Al11.8Ni0.2O19, Sr0.7La0.3Al11.7Ni0.3O19, Sr0.6La0.4Al11.6Ni0.4O19, Sr0.5La0.5Al11.5Ni0.5O19, Sr0.4La0.6Al11.4Ni0.6O19, Sr0.3La0.7Al11.3Ni0.7O19, Sr0.2La0.8Al11.2Ni0.8O19, Sr0.1La0.9Al11.1Ni0.9O19, Ca0.9La0.1Al11.9Ni0.1O19, Ca0.8La0.2Al11.8Ni0.2O19, Ca0.7La0.3Al11.7Ni0.3O19, Ca0.6La0.4Al11.6Ni0.4O19, Ca0.5La0.5Al11.5Ni0.5O19, Ca0.4La0.6Al11.4Ni0.6O19, Ca0.3La0.7Al11.3Ni0.7O19, Ca0.2La0.8Al11.2Ni0.8O19, Ca0.1La0.9Al11.1Ni0.9O19, Ca0.75La0.25Al11.25Ti0.25Ni0.5O19, Ca0.5La0.5Al11Ti0.25Ni0.75O19, Ca0.5La0.5Al10.5Ti0.5NiO19, Ca0.25La0.75Al9.75Ti0.75Ni1.5O19, Ca0.5La0.5Al8.5Ti1.5Ni2O19, LaAl9TiNi2O19, Ca0.5La0.5Al11In0.5Ni0.5O19, Ca0.5La0.5Al11Ga0.5Ni0.5O19, Ca0.5La0.5Al11Ge0.25Ni0.75O19, Ca0.5La0.5Al11Sn0.25Ni0.75O19, Ca0.75La0.25Al11.75Ni0.25O19, Ca0.5Y0.5Al11Ti0.25Ni0.75O19, Ca0.5Ce0.5Al11Ti0.25Ni0.75O19, Ca0.5Pr0.5Al11Ti0.25Ni0.75O19, Ca0.5Na0.5Al10.5TiNi0.5O19, Ca0.5K0.5Al10.5TiNi0.5O19, Ca0.5Rb0.5Al10.5TiNi0.5O19, Ca0.5Cs0.5Al10.5TiNi0.5O19, Ca0.8Mg0.2Al11.6Ti0.2Ni0.2O19, Ca0.5Ba0.5Al8Ti2Ni2O19, Sr0.9Y0.1Al11.9Ni0.1O19, Sr0.8Y0.2Al11.8Ni0.2O19, Sr0.8Ce0.2Al11.8Ni0.2O19, Sr0.8Nd0.2Al11.8Ni0.2O19, Sr0.8Pr0.2Al11.8Ni0.2O19, Ca0.9Y0.1Al11.9Ni0.1O19, Ca0.8Y0.2Al11.8Ni0.2O19, Ca0.7Y0.3Al11.7Ni0.3O19, Ca0.6Y0.4Al11.6Ni0.4O19, Ca0.5La0.5Al10.5Zn0.5Sn0.5Ni0.5O19, Ca0.5La0.5Al10.5Cu0.5Sn0.5Ni0.5O19, Ca0.8Sc0.2Al11.8Ni0.2O19, Ca0.8Yb0.2Al11.8Ni0.2O19, Ca0.7Sr0.3Al11.5Ni0.5O19, CaAl7Ti1.5Ge0.5MgNi2O19, Ca0.9Ce0.1Al11.9Ni0.1O19, Ca0.8Ce0.2Al11.8Ni0.2O19, Ca0.7Ce0.3Al11.7Ni0.3O19, Ca0.6Ce0.4Al11.6Ni0.4O19, Ca0.5Ce0.5Al11.5Ni0.5O19, Ca0.4Ce0.6Al11.4Ni0.6O19, Ca0.3Ce0.7Al11.3Ni0.7O19, Ca0.2Ce0.8Al11.2Ni0.8O19, Ca0.1Ce0.9Al11.1Ni0.9O19, Ca0.9Pr0.1Al11.9Ni0.1O19, Ca0.8Pr0.2Al11.8Ni0.2O19, Ca0.7Pr0.3Al11.7Ni0.3O19, Ca0.6Pr0.4Al11.6Ni0.4O19, Ca0.5Pr0.5Al11.5Ni0.5O19, Ca0.4Pr0.6Al11.4Ni0.6O19, Ca0.3Pr0.7Al11.3Ni0.7O19, Ca0.2Pr0.8Al11.2Ni0.8O19, Ca0.1Pr0.9Al11.1Ni0.9O19, Ca0.9Nd0.1Al11.9Ni0.1O19, Ca0.8Nd0.2Al11.8Ni0.2O19, Ca0.7Nd0.3Al11.7Ni0.3O19, Ca0.6Nd0.4Al11.6Ni0.4O19, Ca0.5Nd0.5Al11.5Ni0.5O19, Ca0.4Nd0.6Al11.4Ni0.6O19, Ca0.3Nd0.7Al11.3Ni0.7O19, Ca0.2Nd0.8Al11.2Ni0.8O19, Ca0.1Nd0.9Al11.1Ni0.9O19, CaAl11.4Nb0.2Ni0.4O19, CaAl11.4Ta0.2Ni0.4O19, CaAl11.4V0.2Ni0.4O19, CaAl11.4Sb0.2Ni0.4O19, CaAl11Zr0.5Ni0.5O19 or CaAl11Te0.5Ni0.5O19.

5. The compound of claim 1, wherein Ma comprises Ni, Co or any combination thereof.

6. The compound of claim 1 wherein Ma is Ni.

7. The compound of claim 1, wherein x+y is less than or equal to 4.

8. The compound of claim 1, wherein y is from 0 to 2.

9. The compound of claim 8, wherein x is from 0.01 to 2.

10. The compound of claim 1, wherein the compound has a blue color.

11. The compound of claim 10, wherein the blue color has a wavelength of from about 440 nm to about 510 nm.

12. The compound of claim 10, wherein the compound has a hibonite crystal structure.

13. The compound of claim 10, wherein Mb comprises Ti.

14. The compound of claim 10, wherein A comprises Ca, La, Sr or any combination thereof.

15. The compound of claim 10, wherein Ma is Co and x is from 0.05 to 1.5.

16. The compound of claim 10, wherein:
Ma is Ni;
Mb is selected from Ti, Ge, Sn or any combination thereof; and
x is from 0.05 to 1.5.

17. The compound of claim 1, wherein Ma comprises at least two metals selected from Ni, Cr, Cu, V, Mn, Co or Fe.

18. The compound of claim 1, wherein Ma comprises V and at least one additional metal selected from Ni, Cr, Cu, Mn, Co or Fe.

19. The compound of claim 1, wherein Ma comprises Cr and at least one additional metal selected from Ni, V, Cu, Mn, Co or Fe.

20. A composition, comprising:
a compound of claim 1; and
at least one additional component.

21. The composition of claim 20, wherein the composition is a paint, an ink, a dye, a glass, a plastic, an emulsion, a fabric, or a cosmetic preparation.

22. The composition of claim 20, wherein the at least one additional component is a binder, a solvent, a catalyst, a thickener, a stabilizer, an emulsifier, a texturizer, an adhesion promoter, a UV stabilizer, a flattener, a preservative, a polymer, a dispersion aid, a plasticizer, a flame retardant, an oxide of a metal, or any combination thereof.

23. The composition of claim 20, wherein the composition is a glass, and the at least one additional component is a metal oxide.

24. The composition of claim 20, further comprising at least one additional compound according to claim 1.

25. A method for making a compound of claim 1, the method comprising:
selecting metals desired in the compound;
providing reactants comprising the selected metals;
combining the reactants in stoichiometric amounts to achieve a desired final ratio of the selected metals in the compound; and
heating the combination of reactants at an effective temperature for an effective period of time to make the compound of claim 1.