Optical Calcite (Iceland Spar), Approximately 2-2.5" Length, Single Piece

• 2-2.5" sample of optical calcite, also known as Iceland Spar
• Optical calcite is birefringent, allowing it to split and transmit beams of light into double images
• Calcite can be used in lessons on mineral hardness, cleavage, and effervescence
• Samples vary naturally, and may not be identical to those pictured
• Great addition to any collection, whether in a classroom or in the home

Looking through this specimen of calcite will have you seeing double. The unique crystal structure of calcite allows it to split and transmit a beam of light into two, displaying two of the same image - this is especially fun to do with a laser pointer. Each specimen exhibits calcite's characteristic rhombohedral cleavage, making it a comprehensive tool for geology classrooms. This sample of calcite is between 2 and 2.5 inches long, and weighs between 2 and 4 ounces. Samples vary naturally, and may not look identical to those pictured. If you reach out to us before you buy, we will send a picture to ensure you are receiving a specimen you'll like.