×

Prase Opal
Prase Opal
☒

Howlite
Howlite
☒



ADD ⊕
Compare
X
Prase Opal
X
Howlite
Physical Properties

Tenacity

Solubility

Durability

Specific Gravity

Fracture

Cleavage

Mohs Hardness

Chemical Composition

 
-
-
-
1.98-2.25
Conchoidal
None
5-6.5
SiO 2 + H 2OUlrich Henn and Claudio C.
 
-
-
-
2.45-2.58
Conchoidal
None
3-3.5
Ca 2B 5SiO 9(OH) 5Michael O’Donoghue , Gems, Sixth Edition (2006) More from other references