I was today years old when I learned minerals could look so.. velvety! Check out this trippy video by Rocks for the Spirit. In their video description they add:

The Malachite shown in this video has a beautiful and mesmerizing chatoyance. Sit back and enjoy the soothing visuals of these velvety Malachite shimmering and glowing under a light. When Malachite forms in radiating spherical shapes like a bunch of grapes it is called botryoidal Malachite. Raw crystalline Malachite forms with many unique surface textures that play with the light. The botryoidal Malachite shown in this video is completely natural and has not been polished. We love the amazing bubbly patterns of these pieces and we hope you do too.