Calcite is naturally colorless or white with a vitreous luster, though the introduction of other compounds during formation can result in a variety of colors. It is best known for its characteristic rhombohedron crystallization but can be found in other forms. Dogtooth Calcite happens when there is an overgrowth of terminations upon the crystal. Scalenohedral crystals resembling canine teeth give these specimens their name.
Chemical composition: Ca[CO3]; Hardness: 3
Hematite is a common iron oxide that is sometimes magnetic. It is iron, grey in color and is found throughout the world near the earth’s surface.
Chemical composition: Fe2O3; Hardness: 5-6
Phantoms are formed when another mineral drops onto a crystal during its growth. The crystal continues to grow, encompassing the foreign mineral which is now in the shape of the crystal during an earlier stage.