micrite
A sedimentary limestone matrix derived from calcite mud.

micrites
plural of micrite

microalteration
A microscopic alteration in the structure of a mineral etc.

microalterations
plural of microalteration

microconglomerate
A sedimentary rock composed of relatively coarse sand grains in a very fine silt or clay matrix

microconglomerates
plural of microconglomerate

microcrystal
A microscopic crystal.

microcrystals
plural of microcrystal

microdiorite
A course-grained igneous rock, of volcanic origin, containing mostly plagioclase feldspar; a rock whose composition is intermediate between andesite and diorite.

microdiorites
plural of microdiorite

microgabbro
A fine-grained igneous rock with the same composition as gabbro but having an ophitic texture; diabase.

microgabbros
plural of microgabbro

microinclusion
A microscopic inclusion (in a mineral etc)

microinclusions
plural of microinclusion

micromineralogy
mineralogy by use of a microscope; the study of microminerals

micromonzonite
monzonite with grain size under 5 millimeters

micromonzonites
plural of micromonzonite

micromount
A mineral specimen that is too small to be appreciated without an optical aid, and is permanently mounted for such a purpose.

micromounts
plural of micromount

micronutrient
A mineral, vitamin or other substance that is essential, even in very small quantities, for growth or metabolism.

micronutrients
plural of micronutrient

micropegmatite
A rock showing under the microscope the structure of pegmatite.

micropegmatites
plural of micropegmatite

microperthite
perthite in which the intergrowths are on a microscopic scale

microperthites
plural of microperthite

microphenocryst
A very small crystal in a fine-grained porphyritic rock.

microphenocrysts
plural of microphenocryst

microquartz
Microcrystalline quartz.

microrotation
rotation of microscopic parts of a fluid, crystal etc.

microrotations
plural of microrotation

microsommite
A hexagonal-trapezohedral mineral containing aluminum, calcium, chlorine, oxygen, potassium, silicon, sodium, and sulfur.

microstratigraphy
The microscopic study of geological strata

microstress
stress in the microstructure of a material, typically in its crystal lattice

microstresses
plural of microstress

microsyenite
syenite with grain size under 5 millimeters.

microsyenites
plural of microsyenite

microvein
A very narrow vein

microveins
plural of microvein

miersite
An isometric-hextetrahedral mineral containing copper, iodine, and silver.

miharaite
An orthorhombic-pyramidal gray mineral containing bismuth, copper, iron, lead, and sulfur.

mijakite
An andesite from the Japanese island of Mijakeshima, porphyritic with phenocrysts of bytownite, augite, hypersthene, and biotite.

mikasaite
A trigonal-rhombohedral mineral containing iron, oxygen, and sulfur.

milarite
A hexagonal-dihexagonal dipyramidal mineral containing aluminum, beryllium, calcium, hydrogen, oxygen, potassium, and silicon.

millisite
A tetragonal-trapezohedral mineral containing aluminum, calcium, hydrogen, oxygen, phosphorus, potassium, and sodium.

mimetene
mimetite

mimetese
A mineral resembling pyromorphite but with some of the phosphoric acid replaced by arsenic acid.

mimetesite
Synonym of mimetite.

mimosite
A melanocratic basaltic rock.
A form of undersaturated picobasalt.

minamiite
A trigonal-hexagonal scalenohedral white mineral containing aluminum, calcium, hydrogen, oxygen, potassium, sodium, and sulfur.

minasragrite
A monoclinic-prismatic blue mineral containing hydrogen, oxygen, sulfur, and vanadium.

minehillite
A hexagonal mineral containing aluminum, calcium, hydrogen, iron, magnesium, manganese, oxygen, potassium, silicon, sodium, and zinc.

mineralist
One versed in minerals; a mineralogist.

mineralists
plural of mineralist

mineralizates
plural of mineralizate

mineralogist
An expert in mineralogy.

mineralogists
plural of mineralogist

mineraloid
A substance that resembles a mineral but does not exhibit crystallinity.

mineraloids
plural of mineraloid

minerology
Dated spelling of mineralogy.

minette
The smallest of regular sizes of portrait photographs.
A mineral deposit consisting of iron ore of sedimentary origin, found in the south of Luxembourg and in Lorraine.

minettes
plural of minette

minguetite
Synonym of stilpnomelane.

minguzzite
A monoclinic-prismatic mineral containing carbon, hydrogen, iron, oxygen, and potassium.

minjiangite
A white mineral found in China.

minrecordite
A trigonal-rhombohedral mineral containing calcium, carbon, oxygen, and zinc.

minverite
A particular hornblende-dolerite mineral.

minyulite
An orthorhombic-pyramidal mineral containing aluminum, fluorine, hydrogen, oxygen, phosphorus, and potassium.

mischio
A colorful variety of marble (metamorphic rock of crystalline limestone).

misenite
A monoclinic mineral containing hydrogen, oxygen, potassium, and sulfur.

miserite
A lilac-pink or red triclinic-pinacoidal rare-earth mineral of interest also for cleaning up radioactive and other wastes and for ceramics.

misopedia
Hatred of, or contempt for, children.

mispickel
The mineral arsenopyrite

mispickels
plural of mispickel

missourite
A leucite-augite rock, resembling ijolite but with leucite in place of nepheline.

missourites
plural of missourite

mitridatite
A monoclinic-prismatic mineral containing calcium, hydrogen, iron, oxygen, and phosphorus.

mitryaevaite
A triclinic-pinacoidal mineral containing aluminum, fluorine, hydrogen, oxygen, phosphorus, and sulfur.

mitscherlichite
A tetragonal-ditetragonal dipyramidal mineral containing chlorine, copper, hydrogen, oxygen, and potassium.

mivvies
plural of mivvy

mivvy
A landlady; a woman who is the owner or manager of a guesthouse.
An (old) woman.
A skillful, smart, adept person.

mizzonite
A variety of scapolite.

mizzonites
plural of mizzonite

moctezumite
A monoclinic-prismatic mineral containing lead, oxygen, tellurium, and uranium.

modderite
An orthorhombic-dipyramidal mineral containing arsenic, cobalt, and iron.

moganite
A crystalline form of silica that has a different crystal structure than that of quartz

mogote
A generally isolated, steep-sided residual hill, composed of limestone, marble, or dolomite and surrounded by nearly flat alluvial plains.

mogotes
plural of mogote

mohawkite
A copper ore and discredited mineral species composed of arsenic and copper, Cu₃As up to Cu₆As.

mohite
A triclinic-pedial greenish gray mineral containing copper, sulfur, and tin.

mohrite
A monoclinic-prismatic light green mineral containing hydrogen, iron, nitrogen, oxygen, and sulfur.

moissanite
Crystalline silicon carbide with various crystalline polymorphs, either naturally-occurring or synthetic.

moissanites
plural of moissanite

molengraaffite
Synonym of lamprophyllite.

moluranite
An amorphous mineral containing hydrogen, molybdenum, oxygen, and uranium.

molybdena
molybdenite

molybdite
An orthorhombic-dipyramidal mineral containing molybdenum and oxygen.

molybdofornacite
A monoclinic-prismatic light green mineral containing arsenic, chromium, copper, hydrogen, lead, molybdenum, oxygen, and phosphorus.

molybdomenite
A monoclinic-prismatic mineral containing lead, oxygen, and selenium.

molybdophyllite
A hexagonal-trapezohedral mineral containing hydrogen, lead, magnesium, oxygen, and silicon.

molybdoscheelite
A molybdiferous scheelite.

molybdosodalite
A sodalite containing molybdenum.

molysite
A trigonal-rhombohedral mineral containing chlorine and iron.

moncheite
A trigonal-hexagonal scalenohedral steel gray mineral containing bismuth, palladium, platinum, and tellurium.

monetite
A triclinic-pinacoidal mineral containing calcium, hydrogen, oxygen, and phosphorus.

mongolite
A tetragonal mineral containing calcium, hydrogen, niobium, oxygen, and silicon.

monheimite
A ferroan variety of smithsonite.

monimolite
An isometric-hexoctahedral mineral containing antimony, calcium, lead, and oxygen.

monocrystal
A single crystal