These three crystals of the mineral quartz show how the same type of mineral can have different colors! Windows to the Universe |
Amethyst crystals from Brazil Courtesy of Corel Photography |
A fossil brachiopod! Oklahoma University/Earth SceinceWorld Imagebank |
This photograph shows several crystals of the mineral, calcite. The crystals in this example are shaped like pyramids. Therefore, the crystals are known as "dogtooth". Courtesy of Corel Photography |
Orthoclase feldspar Windows to the Universe Image |
Gypsum Windows to the Universe/L.Gardiner |
This is a photograph of the mineral, hematite. Hematite contains lots of iron. The chemical formula for hematite is Fe2O3. Windows to the Universe original image |
Crystals of the mineral Pyrite from Peru Courtesy of Corel |
These two examples show the shape of individual quartz crystals. Windows to the Universe Image |