I was the kid who had the rock tumbler in our neighborhood and rock hunting is still something I enjoy with my father to this day. A gemstone or gem, also called a precious or semi-precious stone, is a piece of attractive mineral, which, when cut and polished, is used to make jewelry. However certain rocks, (such as lapis-lazuli) and organic materials (such as amber or jet) are not minerals, but are still used for jewelry, and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone. It is important that I hand pick each stone I purchase because a rare stone can really set apart one of my pieces from the millions of other pieces out there.