Read an Excerpt
Quartz
Hardness: 7 Streak: White
Environment: All environments
What to look for: Light-colored, translucent, glassy and very hard six-sided crystals; also found as masses, veins, and sand
Size: Crystals can be up to fist-sized; masses can be most any size
Color: Colorless to white or gray when pure, but often stained yellow to brown or red; more rarely black or pink
Occurrence: Very common
Notes: Quartz, the most abundant mineral in the earth’s crust, is the first mineral all new collectors should study and be able to identify as it is ubiquitous around the world, including New York. It consists entirely of silica, the silicon- and oxygen-bearing compound that contributes to the formation of hundreds of other minerals, and it is most common as a component of rocks. As such, you’ll encounter quartz most frequently as uninteresting white or gray grains or masses within coarse-grained rocks such as granite, or as the microscopic grains that make up chert. But crystals are not rare, either, and they most often take the form of elongated hexagonal (six-sided) prisms that end with a point, frequently intergrown in groups and lining cavities in rocks. Any river or beach will yield waterworn pebbles of quartz, and glacially deposited pebbles or fragments may be found in any gravelly area. Whatever its form when you find it, quartz is easy to identify due to its distinctively high hardness (it’s typically the hardest mineral you’ll find easily), its translucency, and its conchoidal fracture (when struck, the cracks that form are circular).
Where to Look: Quartz can be found virtually anywhere, especially where there is loose gravel. It’s a common find in rivers and on beaches because it’s hard enough to survive weathering.