Minerals T - Z
Tanzanite
Location: Tanzania, Africa
Variety of: Zoisite
Chemical Composition: Ca2Al3(SiO4)3(OH), Calcium Aluminum Silicate Hydroxide
Hardness: 6.5 - 7
Tigereye
This is a combination of raw and tumbled tigereye. In the tumbled stones, there are yellow, blue, and red tigereye.
Variety of: Quartz
Chemical Composition: NaFe(SiO3)2 Sodium and iron with silicon dioxide (quartz)
Hardness: 6.5 - 7
Black Tourmaline
Alternate October Birthstone
General composition: (Na, Ca)(Li, Mg, Al)(Al, Fe, Mn)6(BO3)3(Si6O18)(OH)4
Hardness: 7.0 - 7.5
Black Tourmaline on quartz
Alternate October Birthstone
General composition: (Na, Ca)(Li, Mg, Al)(Al, Fe, Mn)6(BO3)3(Si6O18)(OH)4
Quartz is: SiO2
Hardness: 7.0 - 7.5
Tourmaline with quartz
Alternate October Birthstone
Location: Brazil
General composition: (Na, Ca)(Li, Mg, Al)(Al, Fe, Mn)6(BO3)3(Si6O18)(OH)4
Quartz is: SiO2
Hardness: 7.0 - 7.5
Tourmaline Rubellite
Alternate October Birthstone
Location: Kunar, Afghanistan
General composition: (Na, Ca)(Li, Mg, Al)(Al, Fe, Mn)6(BO3)3(Si6O18)(OH)4
Hardness: 7.0 - 7.5
Turquoise
Location: Arizona
Chemical Composition: CuAl6(PO4)4(OH)8*5(H2O), Hydrated Copper Aluminum Phosphate
Hardness: 5 - 6
Utah Picture Stone
Location: St. George, Utah
Period: Triassic, estimated as being 150 million years old.
Location: Utal Mts., Russia
Vitreous, resinous green.
Chemical Composition: Ca3Cr2(SiO4)3, Calcium Chromium Silicate
Hardness is 6.5 - 7
Location: Mibladen Mine
Morocco
Sub-resinous/sub-adamantine orange, red, brown, yellow, etc.
Chemical Composition: Pb5(VO4)3Cl , Lead Chlorovanadate
Hardness: 3
Vivianite
Location: Ukraine
Chemical Composition: Fe3(PO4)2-(H2O)8, Hydrated Iron Phosphate
Hardness: 1.5 - 2
Wavellite
Location: Arkansas
Chemical Composition: Al3(PO4)2(OH)3-(H2O)5, Hydrated Aluminum Phosphate Hydroxide
Hardness: 3.5 - 4
Wulfenite
Location: Red Cloud Mine, Arizona
Chemical Composition: PbMoO4, Lead Molybdate
Hardness: 3
Zircon crystal
December Birthstone
Location: Kunar, Afghanistan
Chemical Composition: ZrSiO4, Zirconium Silicate
Hardness: 7.5
