Canary Spring, Mammoth Hot Springs by Diane Renkin. Original public domain image from Flickr https://www.rawpixel.com/image/4038193/photo-image-ocean-nature-mountainFree Image from public domain licenseCalcium carbonate formations, Mammoth Hot Springs by Diane Renkin. Original public domain image from Flickr https://www.rawpixel.com/image/4038184/photo-image-ocean-bee-natureFree Image from public domain licenseCastle Geyser pre-eruption by Diane Renkin. Original public domain image from Flickr https://www.rawpixel.com/image/4038285/photo-image-nature-mountain-waterFree Image from public domain licenseOpalescent Pool, Black Sand Basinby Matt Poyner. Original public domain image from Flickr https://www.rawpixel.com/image/4038817/photo-image-tree-plant-forestFree Image from public domain licenseHeart Spring in Upper Geyser Basinby Diane Renkin. Original public domain image from Flickr https://www.rawpixel.com/image/4038608/photo-image-nature-mountain-waterFree Image from public domain licenseChromatic Pool; Upper Geyser Basinby Matt Poyner. Original public domain image from Flickr https://www.rawpixel.com/image/4038827/photo-image-tree-ocean-plantFree Image from public domain license