Mineral Specimen Images (M)

Macdonaldite: BaCa4[Si16O36(OH)2]·10(H2O)

Comments: Bright white flattened radial macdonaldite aggregate on quartz.
Location: Rush Creek, Fresno County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Macedonite: PbTiO3

Comments: B&W image of pseudo-cubic macedonite grains. (AmMin, v56:387).
Location: Accessory mineral in the amazonite-rich, quartz-syenite veins in Crni Kamen near Prilep, Macedonia. Scale: Picture size 100 x.
© American Mineralogist

Macfallite: Ca2(Mn+++,Al)3(SiO4)(Si2O7)(OH)3  
Johnsenite-(Ce): Na12(Ce,REE,Sr)3Ca6Mn3Zr3W(Si25O73)(CO3)(OH,Cl)2  
Braunite-I: Mn++Mn+++6SiO12

Comments: Tiny - less than 1mm - maroon crystals of mcfallite suspended as inclusions in massive quartz along with larger spots of brown johnsenite-(Ce) and braunite.
Location: Artur mine, Jaguaracu, Minas Gerais, Brazil. Scale: Overall 3 x 2.5 slab.
© Tom Loomis / Dakota Matrix

Mackayite: Fe+++Te2O5(OH)

Comments: Greenish brown crystals of mackayite on matrix.
Location: McGuinnity shaft, Goldfield, Esmeralda County, Nevada, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Mackinawite: (Fe,Ni)S0.9

Comments: Mackinawite inclusions in sulfide ore (polished specimen).
Location: Mackinaw Mine, Snohomish County, Washington, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Macphersonite: Pb4(SO4)(CO3)2(OH)2  
Linarite: PbCu(SO4)(OH)2

Comments: Colorless macphersonite with blue linarite.
Location: Leadhills, Strathclyde, Scotland, UK. Scale: Picture size 3 mm.
© Thomas Witzke / Abraxas-Verlag

Macquartite: Pb3Cu(CrO4)(SiO3)(OH)4·2(H2O)

Comments: Straw-like prismatic yellow micro crystals of macquartite to about 0.5mm on matrix.
Location: Mammoth - St. Anthony mine, Tiger, Pinal Co., Arizona, USA. Scale: Picture size 5 mm.
© Tom Loomis / Dakota Matrix

Macquartite: Pb3Cu(CrO4)(SiO3)(OH)4·2(H2O)

Comments: Bright yellow, prismatic crystals of macquartite in radial sprays to 0.75mm.
Location: Tiger, Mammoth district, Pinal County, Arizona, USA. Scale: Picture size 5 mm.
© Tom Loomis / Dakota Matrix

Madocite: Pb17(Sb,As)16S41

Comments: Gray metallic massive madocite fragment.
Location: Madoc, Ontario, Canada. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Magadiite: NaSi7O13(OH)3·4(H2O)  
Rhodesite: KHCa2Si8O19·5(H2O)

Comments: Earth pale tan massive magadiite with dark yellow crystalline rhodesite.
Location: East Fork, Trinity River, Trinity County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Maghagendorfite: NaMgMn(Fe++,Fe+++)2(PO4)3

Comments: BSE image of graftonite groundmass (Gft) with microgranules of maghagendorfite (Mhg), triphylite (Trp), ludlamite (Lud), and quartz (Qtz). (CanMin, v46:635).
Location: Brissago Granitic Pegmatites, Western Southern Alps, Canton Ticino, Switzerland. Scale: See Image.
© Canadian Mineralogist

Maghemite: gamma-Fe+++2O3

Comments: Fine-grained massive maghemite intermixed with hematite.
Location: Gara Djebilet, Algeria. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Magnesio-arfvedsonite: NaNa2(Mg4Fe++)Si8O22(OH)2  
Vitusite-(Ce): Na3(Ce,La,Nd)(PO4)2

Comments: Translucent beige-colored vitusite-(Ce) in a rim around a black magnesio-arfvedsonite crystal.
Location: Yubileinaya Vein, Karnasurt Mountain, Lovozero Massif, Kola Peninsula, Murmanskaja Oblast', Russia. Scale: Specimen Size 4x3x3 cm.
© John Betts - Fine Minerals

Magnesio-arfvedsonite: NaNa2(Mg4Fe++)Si8O22(OH)2  
Nordite-(La): (Na,Mn)3(Sr,Ca)(La,Ce)(Zn,Mg)Si6O17

Comments: Large tabular crystal of brownish nordite-(La). Accessory minerals are white chalky natrolite and black prismatic magnesioarfvedsonite.
Location: Kirovskii apatite mine (Kirovsky Mine; Kirov Mine), Kukisvumchorr Mt, Khibiny Massif, Kola Peninsula, Murmanskaja Oblast', Northern Region, Russia. Scale: FOV is 12x10 mm.
© Pavel M. Kartashov

Magnesioanthophyllite: (Mg,Fe++)7Si8O22(OH)2  
Anthophyllite: [ ]Mg7Si8O22(OH)2

Comments: Schistose amphibolite rock composed primarily of anthophyllite (magnesioanthophyllite is now considered to be anthophyllite).
Location: Winchester, Riverside County, California, USA. Scale: See Image.
© Rruff Database

Magnesioastrophyllite: K2Na[Na(Fe++,Fe+++,Mn)Mg2]Ti2Si8O26(OH)4F

Comments: White chalky mass of magnesioastrophyllite in matrix.
Location: N'orkpakhk Mt., Khibiny Massif, Kola Peninsula, Russia. Scale: Specimen Size 35 x 25 x 10 mm.
© Sergey Vasiliev / Systematic Mineralogy

Magnesioaubertite: (Mg,Cu)Al(SO4)2Cl·14(H2O)  
Pickeringite: MgAl2(SO4)4·22(H2O)

Comments: Aqua crystalline magnesioaubertite with white pickeringite.
Location: Grotto di Faraglione, Vulcano, Sicily, Italy. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Magnesiochromite: MgCr2O4

Comments: Black crystalline magnesiochromite grains in serpentinite.
Location: Red Pit, Fulton Township, Lancaster County, Pennsylvania, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Magnesioclinoholmquistite: Li2(Mg,Fe++)3Al2Si8O22(OH)2  
Clinoholmquistite: [ ](Li2Mg3Al2)Si8O22(OH)2  
Fluoro-sodic-pedrizite: NaLi2(Mg2Al2Li)?5Si8O22F2

Comments: Dark blue fibrous clinoholmquistite with radiating structure, variety magnesioclinoholmquistite. Clinoholmsquitite may be a new aphibole, fluoro-sodic-pedrizite..
Location: Near Murun, Republic of Sakha, Siberia, Russia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Magnesiocopiapite: MgFe+++4(SO4)6(OH)2·20(H2O)  
Guildite: CuFe+++(SO4)2(OH)·4(H2O)

Comments: Brown granular guildite with greenish yellow magnesiocopiapite.
Location: United Verde Mine, Jerome, Yavapai County, Arizona, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species