In geology, druse refers to a coating of fine crystals on a rock fracture surface or vein or within a vug or geode. Generally, it is possible to find drusy natural gemstones 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.

Because of its sparkling appearance, druse is sometimes used in jewelry making. Druse is used with a variety of natural gemstones including agate, crystalline quartz and many more.

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