Minerals D - E

 
Datolite

Location: USA
Chemical Composition: CaBSiO4(OH)
Hardness: 5 - 5.5

 

Dioptase

Location: Romania, the United States, Argentina, Chile, the Congo Republic, the Democratic Republic of the Congo, Namibia, Angola, Zimbabwe, Russia and more
Chemical Composition: CuSiO3 -H2O, Hydrated copper silicate
Hardness: 5 (harder than other green copper minerals)

 

(Cobaltoan) Dolomite

Location: People's Rep. of Congo, Africa
Chemical Composition: CaMg(CO3)2, Calcium Magnesium Carbonate
Hardness is 3.5 - 4

 

Pink Kona Dolomite
"Michigan Picture Rock"


Location: Michigan, USA
Chemical Composition: CaMg(CO3)2, Calcium Magnesium Carbonate
Hardness is 3.5 - 4

 

Dugway Geodes

Can belong to both the Chalcedony and Quartz Species.
Location: Utah
Chemical Composition: SiO2
Hardness: 7

 

Elbaite

Location: Russia, Afghanistan, Pakistan, Madagascar, Mozambique, Namibia, the United States, Brazil, and more
Variety of: Tourmaline
Chemical Composition: Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4
Hardness: 7.5

 

Emerald

May Birthstone
Location: Zambia, Colombia, Brazil, Pakistan, Afghanistan, Russia, Australia, United States
Variety of: Beryl 
Chemical Composition: Be3 Al2 Si6 O18
Hardness: 7.5 - 8

 

Eudialite

Location: Canada, Russia, Brazil, Greenland, Norway, and Arkansas
Chemical Composition: Na4(Ca, Ce, Fe, Mn)2ZrSi6O17(OH, Cl)2, Sodium Calcium Cerium Iron Manganese Zirconium Silicate Hydroxide Chloride
Hardness is: 5 - 5.5