What Is Drusy?

Definition

• A drusy is sets of tiny crystals of minerals that form on the surface of another stone. There are many types of drusy, because there are many types of minerals. Each type of drusy has particular characteristics, such as crystal size, luster and color. Quartz is one of the most common drusy types because of the prevalence of silica throughout the world. No matter what mineral forms the drusy, the overall appearance usually resembles that of sugar. The tiny crystals are considered beautiful because, like large gemstones, they glitter and catch rays of light.

Origin

• The geological process that forms a druse, the layer of crystals on the rock, occurs when water brings minerals onto a rock's surface. When the water evaporates, cooling occurs and the minerals are left behind to form crystals on top of the rock. Depending on the minerals, drusys can be almost any color of the rainbow, including white, pink, blue, purple, green or black.

Uses

• The most common use for drusy is in jewelry. The glittery stone is used in pendants, earrings, bracelets and other ornaments. Some people collect pieces of drusy because the drusy is beautiful or as geological specimens.

Cost

• A piece of jewelry prepared with drusy averages between $50 and $200, but this range is dependent on the size of the piece of drusy, the mineral that forms the drusy (its rarity) and the other materials used to create the piece of jewelry, such as gold. Pieces of drusy that are used in jewelry are sometimes treated with a layer of metal to improve their durability, color or luster. The metals used for this include gold, titanium and platinum. This process is called physical vapor disposition. It can impact the cost of a piece of drusy.

Geography

• Drusy can be found in any location in which there is a place for water to collect and evaporate on rock. It most often appears along river beds and shorelines. However, the minerals available for drusy formation vary depending on geological location. It therefore is helpful for collectors, whether commercial or otherwise, to be aware of the minerals common to an area when they look for a particular type of drusy.