nyuuzyou/wikis huggingface dataset:
Onion

== Description ==
A round edible bulb, Allium cepa, whose outer skins have been used to produce a dye. The dried skins are removed from the onion and boiled in water to produce shades of yellow, brown, and green. The flesh of onions makes a paler yellow and young sprouts give a vivid yellow. Historically, onion skins have been used for dyeing by the ancient Greeks, Persians, Egyptians, and African tribes.
* See also [Uemera Dye Archive (Tamanegi)] 
== Synonyms and Related Terms ==
Allium cepa; Natural Yellow 10; Zwiebel (Deut.); cebolla común (Esp.); oignon (Fr.); cipolla (It.); ui (Ned.); cebula zwyczajna (Pol.); cebola (Port.); gul lök (Sven.)
== Resources and Citations ==
* R.J. Adrosko, Natural Dyes in the United States, Smithsonian Institution Press, Washington, DC, 1968
* Helmut Schweppe, Schweppe color collection index and information book
* J. Thornton, 'The Use of Dyes and Colored Varnishes in Wood Polychromy', Painted Wood: History and Conservation, The Getty Conservation Insitute, Los Angeles, 1998
* Wikipedia: http://en.wikipedia.org/wiki/Onion (Accessed Mar. 20, 2006) -for non-English terms
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 852
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Onionskin paper

== Description ==
A thin, strong, translucent writing paper. Onionskin paper is made from bleached, and hydrated chemical pulp and/or cotton fibers. It is sized with rosin, starch, or glue then supercalendered to produce a glazed or cockle finish. It takes ink well and erases easily. Onionskin paper is used for low bulk operations, such as airmail correspondence. It used to be commonly used for making multiple typewritten duplicates with carbon copy paper.
== Synonyms and Related Terms ==
onion-skin paper (Br.); pelure surglacée (Fr.)
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 576
* Boise Cascade Paper Group, The Paper Handbook, Boise Cascade, Portland OR, 1989
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
* Book and Paper Group, Paper Conservation Catalog, AIC, 1984, 1989
* The Dictionary of Paper, American Paper Institute, New York, Fourth Edition, 1980
* E.J.LaBarre, Dictionary and Encyclopedia of Paper and Paper-making, Swets & Zeitlinger, Amsterdam, 1969
* Art and Architecture Thesaurus Online, https://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
Category:Materials database
Onji - left (204 L)

[[[SliderGallery rightalign|Uemura_07-09-2009_204.jpg~Normal|Uemura_07-09-2009_204_UV.jpg~UV]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 204
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 3rd shelf
|-	
! scope="row"|Sample location
| left (204 L)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| pale brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| 遠志 : Onji
|-	
! scope="row"|Dyestuff (botanical name)
| Polygala tenuifolia Willd.
|-	
! scope="row"|Plant part
| root /dried
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| iron
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| Actual use of this plant as dyestuff was unknown, though listed as medicinal plant in the Shinnhonzoukyo () from 300 BC - 200 AD, China.
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onji - right (204 R)

[[[SliderGallery rightalign|Uemura_07-09-2009_204.jpg~Normal|Uemura_07-09-2009_204_UV.jpg~UV]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 204
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 3rd shelf
|-	
! scope="row"|Sample location
| right (204 R)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| light greenish beige
|-	
! scope="row"|Dyestuff (Japanese common name)
| 遠志 : Onji
|-	
! scope="row"|Dyestuff (botanical name)
| Polygala tenuifolia Willd.
|-	
! scope="row"|Plant part
| root /dried
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| lime water
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| Actual use of this plant as dyestuff was unknown, though listed as medicinal plant in the Shinnhonzoukyo () from 300 BC - 200 AD, China.
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - center (49 C)

[[[SliderGallery rightalign|Uemura_04-16-2009_049.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 49
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| center (49 C)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| pale brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. var. cuspidate
|-	
! scope="row"|Plant part
| unspecified
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| lime water (supernate)
|-	
! scope="row"|Other auxiliary agent
| ash water
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - left (47 L)

[[[SliderGallery rightalign|Uemura_04-16-2009_047.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 47
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| left (47 L)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| pale brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. var. cuspidate
|-	
! scope="row"|Plant part
| branch /dried
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| -
|-	
! scope="row"|Other auxiliary agent
| ash water
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - left (48 L)

[[[SliderGallery rightalign|Uemura_04-16-2009_048.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 48
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| left (48 L)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| dark brown (lighter)
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. var. cuspidate
|-	
! scope="row"|Plant part
| unspecified
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| iron
|-	
! scope="row"|Other auxiliary agent
| ash water
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - left (50 L)

[[[SliderGallery rightalign|Uemura_04-16-2009_050.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 50
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| left (50 L)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| pale reddish brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. var. cuspidate
|-	
! scope="row"|Plant part
| heartwood /dried (?)
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| lime
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| The dyed color appeared to be similar whether ash water or lime is added to the dye bath.
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - right (47 R)

[[[SliderGallery rightalign|Uemura_04-16-2009_047.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 47
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| right (47 R)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| pale reddish brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. var. cuspidate
|-	
! scope="row"|Plant part
| branch /dried
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| -
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| Onko () is also called Kiyaragi () or Yamasuoh (), and is a variant of Japanese Yew, called Ichii () and Araragi (). The resultant color of Ichii would be same. The plant looks similar to Brazilwood, which is probably the reason why the plant is alternatively called Yamasuoh (= mountain-Brazilwood). The Ainu () people used this plant for dyeing reds.
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - right (48 R)

[[[SliderGallery rightalign|Uemura_04-16-2009_048.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 48
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| right (48 R)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| dark brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. Var. cuspidate
|-	
! scope="row"|Plant part
| unspecified
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| iron
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onko (Japanese Yew) - right (50 R)

[[[SliderGallery rightalign|Uemura_04-16-2009_050.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 50
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 1st shelf
|-	
! scope="row"|Sample location
| right (50 R)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| yellow brown
|-	
! scope="row"|Dyestuff (Japanese common name)
| おんこ : Onko
|-	
! scope="row"|Dye (English common name)
| Japanese Yew
|-	
! scope="row"|Dyestuff (botanical name)
| Taxus cuspidate Siebold et Zucc. var. cuspidate
|-	
! scope="row"|Plant part
| heartwood /dried (?)
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| alum
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Onyx

== Description ==
A variety of agate that has parallel, alternating bands of chalcedony and opal. The bands are usually colored black/white or red/white. In ancient times, the stones were available in Egypt, Arabia, and India. Onyx was often used as a gemstone in the production of cameos and intaglios. Onyx is also used as an ornamental building stone and for decorative items such as table tops, lamp bases, and small boxes. It was popularly used for geometric patterns in Art Deco designs of the 1920s. Limestone onyx, also called onyx marble, dark layers of impurities and polishes to a high gloss. Mexican onyx is a banded limestone made from stalactites. Argentine onyx is a dark-green stone. Sardonyx has layers of sard (brownish) alternating with lighter-color layers of carnelian (red).
== Synonyms and Related Terms ==
agate; onyx marble; sardonyx; Mexican onyx; Onyx (Deut.); ónice (Esp.); onyx(Fr.); onyks (Pol.); onix (Port.); onyx (Ned.)
== Risks ==
Inhalation of dust may be toxic resulting in silicosis.
== Physical and Chemical Properties ==
* Composition = SiO2
* No visible crystals 
* Fracture = conchoidal, uneven, splintery 
* Luster = waxy to vitreous
* Streak = white 
* Fluorescence = generally inert
* Pleochroism = absent
* Mohs Hardness = 6.5 - 7.0
* Density = 2.6
* Refractive Index = 1.530 - 1.543
* Birefringence = 0.004 - 0.009
== Comparisons ==
== Resources and Citations ==
* Gem Identification Lab Manual, Gemological Institute of America, 2016.
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 565
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Jack Odgen, Jewellery of the Ancient World, Rizzoli International Publications Inc., New York City, 1982
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* A.Lucas, J.R.Harris, Ancient Egyptian Materials and Industries, Edward Arnold Publishers Ltd., London, 4th edition, 1962
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
* Website: http://www.marble-institute.com
* Wikipedia: Onyx varieties (Accessed Sept. 14, 2005 and Dec 2022)
* Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
* Tom Rowland, Noel Riley, A-Z Guide to Cleaning, Conserving and Repairing Antiques, Constable and Co., Ltd., London, 1981
Category:Materials database
Ooid

== Description ==
Spherical to ellipsoidal body which may or may not have a nucleus and has concentric or radial structure or both. Ooids are is usually calcareous, but may be siliceous, hematitic, or of other composition. A sedimentary rock containing numerous ooid grains that are cemented together is called an oolite. See also oolitic limestone.
== Synonyms and Related Terms ==
oolith; oólito (Port.)
== Physical and Chemical Properties ==
* Usually less than 2 mm in size
==Resources and Citations==
* José Delgado Rodrigues, LNEC, Submitted information 2009.
Category:Materials database
Oolitic limestone

== Description ==
A limestone, or other sedimentary rock, that contains oolites, i.e. rounded calcitic stones. Coarse-grain oolites are about the size of peas and are called pisolites. Fine-grain oolites are about the size of fish roe. Oolites are thought to be the calcified excrement of worms.
== Synonyms and Related Terms ==
eggstone; oolitic freestone; oolitic limestone; Bedford limestone; Shadow Vein; calcaire oolithique (Fr.); calcário oolítico (Port.); Oolithischer Kalkstein (Deut.); oolitische kalksteen (Ned.)
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 455
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Ooze

== Description ==
1) An obsolete term for a solution of vegetable tannins (Roberts and Etherington 1982). Also called wooze. 
2) A soft, muddy sediment.
== Synonyms and Related Terms ==
wooze
==Resources and Citations==
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
* Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Opacifier

== Description ==
A material added to a ceramic glaze or enamels to increase its optical density, i.e., make it more opaque. Opacifiers can also make the glaze shinier, more homogeneous and less likely to craze. Tin oxide is one of the best opacifiers for ceramics and it also acts as a flux. Zirconium oxide is also used as a less expensive alternative. Titanium dioxide adds hardness and chemical resistance to the enamels. Some pigments, such as cobalt oxide (blue), platinum dioxide (gray), and lead chromate (red/green) also act as opacifiers.
== Synonyms and Related Terms ==
opacifiant (Fr.); opacizzante (It.); glansmiddel (Ned.); opacificante (Port.); Lufax [Rohm & Haas]; Zircopax [Titanium Alloy Mfg.]; Opax [Titanium Alloy Mfg.]; Superpax [Titanium Alloy Mfg.]; Ultrox [M&T Chemicals]
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 562
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Opacimeter

== Description ==
A device used to measure opacity. An opacimeter is used to measure the optical density of paper. The device gives the light reflectance ratio for two readings collected when a piece of paper placed over a black background and then a white background.
== Synonyms and Related Terms ==
Bausch and Lomb Opacimeter
==Resources and Citations==
* Boise Cascade Paper Group, The Paper Handbook, Boise Cascade, Portland OR, 1989
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
* E.J.LaBarre, Dictionary and Encyclopedia of Paper and Paper-making, Swets & Zeitlinger, Amsterdam, 1969
Category:Materials database
Opacity

== Description ==
The ability of a material to block the passage of light. Opacity is the opposite of transmittance. Both are measured as optical density. In paints, the opacity of a pigment indicates its ability to cover, or hide, a color beneath it. An opaque paper can be printed on two sides without image interference. Ceramic glazes must be opaque to cover the clay body. In photography, opacity indicates that amount of light absorbed by the emulsion.
== Synonyms and Related Terms ==
Opazität (Deut.); opacité (Fr.);
Category:Materials database
Opal glass

== Description ==
A milky white, translucent glass. Opal, or opalescent, glass was first made in the mid-1800s but not patented until 1880 by Louis Tiffany. Tiffany and J. La Farge prepared large sheets of opal glass for use in windows. Opal glass is made white by the addition of calcium phosphate (bone ash) and opalescent by the addition of fluorides (fluorspar, cryolite, or lepidolite) and/or arsenic. Opal glass was used for light shades, table tops, and cosmetic jars.
== Synonyms and Related Terms ==
opalescent glass; white glass; vidrio opal (Esp.); opalina (Esp.); opaline (Fr.); opaalglas (Ned.); vidro opala (Port.); bone glass; flint glass; alabaster; opaline; Vitrolite
== Resources and Citations ==
* J.Sloan, "American Opalescent Window Glass: Composition and Deterioration Issues" in ICOM Preprints, Lyon, 1999. p.803-808.
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 365
* Susan E. Schur, Conservation Terminology: A review of Past & Current Nomenclature of Materials, Technology and Conservation, Spring (p.34-39); Summer (p.35-38); Fall (p.25-36), 1985
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
Category:Materials database
Opalescence

== Description ==
An optical phenomena that occurs in gemstone opals and appears as a milky iridescence. Opalescence is produced natural by the reflection and refraction of light through the spacing and layering of silicon dioxide spheres and water inclusions. An opalescent glaze or glass can be induced by added boron, fluoride or arsenic compounds to the starting mixture.
== Synonyms and Related Terms ==
* opalescence (noun: definition = reflecting or changing light like an opal)
* opalescent (adjective: definition = reflecting iridescence)
Category:Materials database
Opaline Dry Cleaning Pad

== Description ==
[Durasol Chemical] A brand name for a dry cleaning pad composed of a vulcanized rubber base filled with magnesium silicate. Opaline has been used to dry clean paper. The eraser can leave tiny yellowish crumbs on the surface that darken slightly with age.
==Resources and Citations==
* E.J.Pearlstein, D.Cabelli, A.King, N.Indictor "Effects of Eraser Treatment on Paper" JAIC 22:1-12, 1982.
Category:Materials database
Opaline granite

== Description ==
A medium-grain, hard granite quarried in Texas (Lent 1925). Opaline granite has a beige and brown background with sky-blue quartz crystals. It was used for decoration and buildings.
==Resources and Citations==
* Frank A. Lent, Trade names and Descriptions of Marbles, Limestones, Sandstones, Granites and Other Building Stones Quarried in the United States Canada and other Countries., Stone Publishing Co, New York, 1925
Category:Materials database
Opax

== Description ==
[TAM, a Cookson Co.] A brand name for a zirconium oxide opacifier used in ceramic glazes. Opax also contains small amounts of silica, sodium oxide and alumina. It is used for hard-glaze dinnerware and wall tiles (Brady 1971).
==Resources and Citations==
* G.S.Brady, Materials Handbook, 10th edition, McGraw-Hill, New York, 1971.
Category:Materials database
Ophicarbonate

== Description ==
A mixed rock that contains of serpentine (magnesium silicate) and calcite (calcium carbonate) cemented together with red iron oxide (ferrous oxide). Ophicarbonate stones have fragments of red, white and green colors. The stones polish to a high gloss, which has led to them being occasionally mislabeled as marble. However, the ophicarbonate rocks are fragile and unsuited for sculpture because of their multicomponent structure.
== Synonyms and Related Terms ==
antique green; Levanto red
Category:Materials database
Opopanax

== Description ==
A strong smelling gum-resin obtained from the roots of perennial plants, Opopanax chironium, native to Asia Minor and the Balkans. Opopanax dries to forms yellow or reddish lumps or tears. Most opopanax resin sold today is obtained from trees of the Commiphora species (i.e. myrrh), such as C. kataf, and C.erythraea.
== Synonyms and Related Terms ==
Opopanax chironium
==Resources and Citations==
* M.Serpico, R.White, "Resins, Amber and Bitumen" in Ancient Egyptian Materials and Technology, P.Nicholson, I.Shaw (eds.), Cambridge University Press, 2000, p. 430-474.
Category:Materials database