Mineral Specimen Images (M)

Maucherite: Ni11As8

Comments: Reddish, semi-metallic aggregate of feathery maucherite crystals on matrix.
Location: Cobalt, Ontario, Canada. Scale: Picture size 2 mm.
© Reiner Mielke

Maucherite: Ni11As8  
Argentopentlandite: Ag(Fe,Ni)8S8

Comments: Reflected light image of a polished section containing argentopentlandite (AgP) with galena (G), native silver (Ag), chalcopyrite (Ch) and maucherite (M).
Location: Silver City, Ontonagon Co., Michigan, USA. Scale: Picture Size 900 µm.
© Jeff Weissman / Photographic Guide to Mineral Species

Mawbyite: Pb(Fe+++Zn)2(AsO4)2(OH,H2O)2

Comments: Brown crystalline mawbyite in quartz.
Location: Kintore Open Cut, Broken Hill, New South Wales, Australia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mawsonite: Cu+6Fe+++2Sn++++S8

Comments: Mawsonite inclusions in brassy yellow chalcopyrite.
Location: Mount Lyell, Queenstown, Tasmania, Australia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mawsonite: Cu+6Fe+++2Sn++++S8

Comments: Polished Secton (PPL) showing traces of digenite (dig) throughout massive bornite (bn). A large grain of mawsonite (mw) is present at the bottom right.
Location: Kidd Creek Volcanogenic Massive Sulfide deposit, Western Abitibi Subprovince, Timmins, Ontario, Canada. Scale: Picture Size 0.5 mm.
© National Resouces of Canada

Maxwellite: NaFe+++(AsO4)F

Comments: Minute red translucent maxwellite crystal in rhyolite.
Location: Squaw Creek Tin Mine, Black Range, Catron County, New Mexico, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mayenite: Ca12Al14O33

Comments: Gray mayenite grains in matrix.
Location: Bellerberg, Eifel, Germany. Scale: Picture size 1 mm.
© Diederik Visser

Mazzettiite: Ag3HgPbSbTe5

Comments: Back-scattered electron photograph (SEM) of mazzettiite (M), associated with altaite (A), galena (G) and quartz (Q).
Location: Museum specimen in the Mineralogical Collection of the Institut royal des Sciences naturelles de Belgique, Bruxelles (Belgium). Findlay Gulch, Saguache Co., Colorado, USA. Scale: See Image.
© Canadian Mineralogist

Mazzite-Mg: K2CaMg2(Al,Si)36O72·28(H2O)

Comments: Clear colorless microcrystals and crystalline mazzite in vug.
Location: Mont Simiol, Loire, France. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mazzite-Na: Na8Al8Si28O72?30H2O

Comments: Silky mazzite-Na fibers filling a cavity in basalt.
Location: Open pit of the U.S. Borax mine at Boron, California. Scale: Specimen size 5 mm.
© American Mineralogist

Mbobomkulite: (Ni,Cu)Al4(NO3,SO4)2(OH)12·3(H2O)

Comments: White earthy mbobomkulite.
Location: Jomac Uranium mine, White Canyon, San Juan Co., Utah, USA. Scale: Picture size 3.5 mm.
© Thomas Witzke / Abraxas-Verlag

Mcallisterite: Mg2B12O14(OH)12·9(H2O)

Comments: Tan to white opaque porous aggregate of mcallisterite.
Location: Qinghai, China. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mcalpineite: Cu++3Te++++++O6·(H2O)

Comments: Dark green crystals of mcalpineite in matrix.
Location: Centennial Eureka Mine, Tintic District, Juab Co., Utah, USA. Scale: Picture size 1.7 mm.
© Thomas Witzke / Abraxas-Verlag

Mcgillite: (Mn,Fe++)8Si6O15(OH)8Cl2

Comments: Pink crystalline mcgillite with galena.
Location: Near Kimberley, Kootenay District, British Columbia, Canada. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mcgovernite: Mn9Mg4Zn2As2Si2O17(OH)14

Comments: Golden sub-metallic micaceous mcgovernite with black franklinite, red willemite, and white calcite.
Location: Franklin, Sussex County, New Jersey, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mcguinnessite: (Mg,Cu)2(CO3)(OH)2

Comments: Cotton ball clusters of vivid blue mcguinnessite crystals on matrix.
Location: Miners Ridge, Red Mountain, Mendocino County, California, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Mcguinnessite: (Mg,Cu)2(CO3)(OH)2  
Vuagnatite: CaAlSiO4(OH)

Comments: Translucent colorless vuagnatite microcrystals with mcguinnessite.
Location: Near Red Mountain, Mendocino County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mckelveyite-(Y): NaCa(Ba,Sr)3(Y,REE)(CO3)6·3(H2O)

Comments: Vitreous, gray, mckelveyite crystals in matrix.
Location: Mt. Kukisvumchorr, Khibiny Massif, Kola Peninsula, Russia. Scale: Specimen Size 2.8 x 1.9 x 1.9 cm.
© John Veevaert

Mckinstryite: (Ag,Cu)2S  
Silver: Ag

Comments: Black metallic massive mckinstryite with wire silver.
Location: Peregrina Mine, Guanajuato, Mexico. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mcnearite: NaCa5H4(AsO4)5·4(H2O)

Comments: Crystalline mcnearite micro botryoids on matrix.
Location: Gabbe Gottes, Sainte-Marie-aux-Mines, Haute-Rhin, France. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species