I hand cut this cabochon. Measurements are in the title in mm. A triangle shape with a satin matte finish. This material is found around Kelowna, British Columbia and it is famous for looking dramatically like a rugged ocean coast! I've heard it called "BC Ocean Stone" or "BC Ocean Jasper" and also "Ocean Picture Jasper." I've also seen a seller call it "Surfer Jasper." Those are only location and descriptive names and this stone is NOT RELATED at all to "Ocean Jasper" from Madagascar. I've only seen slabs or rough for sale a few times in my life and I've bought some each time I saw it! From what I have been able to test and research, the blue is neither agate or jasper but it IS a variety of quartz. The best analysis I've found is that it is a silicated (turned into quartz) serpentinite. I got 10 slabs of it in Tucson in the Winter of 2017 and when it's out, it's out, until I can hopefully come across more. I currently know of no one who has any more quality stock of rough or slabs. If you have some or know of some, let me know! According to wikipedia... "Serpentinite is a rock composed of one or more serpentine group minerals. Minerals in this group are formed by serpentinization, a hydration and metamorphic transformation of ultramafic rock from the Earth's mantle. The mineral alteration is particularly important at the sea floor at tectonic plate boundaries." So the original formation was replaced by quartz. It's not as hard as an agate or jasper. The matrix rocks of the "shore" are just rock. LOL. If you want to see ALL of my inventory of custom cut focal beads, cabochons, chains, and jewelry you will find all of it on my website. I have bargain auctions in my eBay store at least once a month. I have an Etsy store as well as the website, but Etsy will only showcase the most recent 4 months work, while the entire stock will always be on the website. Sign up for my mailing list from the website, where you can also see my show and lecture schedule. Feel free to like my DVHdesigns page on Facebook where you can see my complete inventory as well!