Rough Optical Calcite with Inclusions / 1.5-2.5" AVG - 1 KILO LOT Valentine's Day Pieces measure approximately 40 to

Pieces measure approximately 40 to 50 millimeters (AVERAGE SIZE)

Pieces measure approximately 0

Unlike its more traditionally blue

Average size range: 20 to 70 millimeters

Pieces measure approximately 3 to 4 inches (AVERAGE SIZE)

Rough Optical Calcite with Inclusions / 1.5-2.5" AVG - 1 KILO LOT Valentine's Day Pieces measure approximately 40 toQuantity: 1 kilogram Average size range: 1. 5 to 2. 5 inches Optical calcite, also known as Iceland spar, is a special type of calcite that forms extremely clear and somewhat rectangular crystals. For centuries, sailors would use these crystals to help determine the direction of the sun on cloudy days for navigation.