Sometimes spelled druzy, druse or drusies, all these terms refer to tiny crystals that form within or on the surface of other minerals. The most common drusy is quartz (agate or chalcedony), but many other gemstone drusy types exist, including uvarovite garnet, rainbow pyrite, rainbow hematite, hemimorphite, chrysocolla, calcite, dolomite, sphalerite, demantoid garnet, melanite garnet, azurite, dioptase, turquoise and vanadinite.
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