Pyrite with fluorescent calcite from the USA. Well-formed pyrite crystals with bright metallic luster occur on a fine-grained matrix, associated with minor calcite showing strong fluorescence under UV light. Ex collection: Gordon C. Nelson. This specimen comes from a reputable source and has not been altered or treated in any way—what you see is its natural form. The photos are taken under daylight-equivalent LED lighting to show the specimen as accurately as possible. Please note: some colors can be difficult to capture accurately in photographs. I do my best to present the specimen faithfully. All items are professionally packed and shipped with tracking. I have many years of experience in international mineral sales and strive to provide accurate descriptions and high-quality service. Feel free to reach out with any questions—I'm happy to help.