I ordered the Jade one and am expecting it monday. I did find this one page that compares the different brands.
This one compares the different brands.
biomatsreviewed.homestead.com/BIOMAT-VS-TheraSage-VS-Vita-Mat.htmlThis one compares the jade and amethyst.
biomatsreviewed.homestead.com/Jade-VS-AMETHYST-MATS.htmlI did read that Biomat originally used jade and then switched to amethyst because they felt it penetrated the body better. I am still on the lookout for a amethyst biomat. Fingers crossed.