Fine-grained massive sulfide
![Two photos show the same rocks, one with an ultraviolet light shining on it to reveal fluorescent minerals.](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/media/images/Sulfide1_web.gif?itok=VKM1mYxT)
Detailed Description
Close up of fine-grained massive sulfide containing the primary minerals pyrrhotite, sphalerite, and barite. Weathering has produced secondary minerals, including iron oxide and possibly jarosite. Shiny image shows the same rock under an ultraviolet light source, revealing the minerals that fluoresce under the light.
Sources/Usage
Public Domain.