Where does most gem-quality topaz come from?

Most gem-quality topaz is primarily found in pegmatites, which are coarse-grained igneous rocks that form during the final stages of magma crystallization. These pegmatites are known for their ability to host large crystals and various minerals, including topaz. The conditions under which pegmatites form often lead to the development of high-quality gemstones.

In contrapart, while riverbeds, metamorphic rocks, and volcanic deposits can contain various minerals, they are not typically associated with the formation of high-quality topaz. Riverbeds might host eroded gems from other sources but lack the hydrothermal conditions necessary for topaz growth. Metamorphic rocks can alter existing mineral structures but are not known to be significant sources of gem-quality topaz. Lastly, volcanic deposits might yield some minerals but are more commonly associated with other gemstones, not topaz. Thus, pegmatites serve as the primary source for sourcing high-caliber topaz.