Oligoclase Var. Sunstone

Tvedestrand, in southern Norway, is a sunstone locality known for its warm reddish-brown color and metallic flashes. This material is oligoclase feldspar, and its shimmering effect comes from tiny, aligned hematite inclusions that reflect light. The classic occurrence at Østerådalen was discovered in 1842, where sunstone formed in a pegmatite within gneiss alongside clear quartz. The deposit is now considered exhausted, making specimens from this locality an interesting part of Norway’s mineral-collecting history. Ex. Westenberger Collection.