Presentation :
Carnelian is a red variety of chalcedony, which itself is a cryptocrystalline variety of quartz. The formula for this family of minerals is SiO2. Carnelian owes its color to he...
Presentation :
Name :
Aventurine and Aventurine Quartz: (Variety of Quartz or Quartzite)
Etymology:
From Italian avventura = chance | NB: "Aventurine", when written alone, descri...
Presentation:
Names) :
Bull's eye (variety of quartz).
Etymology:
Based on color and appearance.
Group, Family:
Quartz family (Microcrystalline/Cryptocrystalline).
...
Presentation :
Names) :
Hawk's eye (quartz variety).
Etymology:
According to the characteristic color and appearance.
Group, Family:
Quartz family (Microcrystalline/Crypt...
