Sliced agate

Category: Quartz variety

 

Formula: (repeating unit) SiO2 silicon dioxide

 

Color: White to grey, light blue, orange to red, black. banded

 

Crystal habit: Cryptocrystalline silica

 

Crystal system: Rhombohedral Microcrystalline

 

Mohs scale hardness: 6.5–7

 

Luster: Waxy

 

Diaphaneity: Translucent

 

Specific gravity: 2.58–2.64

 

Refractive index: 1.530–1.540

 

Birefringence: up to +0.004 (B-G)

 

Pleochroism: Absent

Done