Its is basically a buff-top shape. Crack-free and extremely clean, front and back. There are a few spots of sand on the side. As ever, this is a solid, untreated, All-Natural gemstone. PLEASE NOTE: you are looking at enlarged images of a small gemstone.Flaws or blemishes may not be visable to the naked eye! White lines or spots that do not remain in the same place are reflections from the highly polished surface. 16ct Solid Black Opal BLUE & GREEN Freeform from Lightning Ridge" is in sale since Monday, March 9, 2020. This item is in the category "Jewelry & Watches\Loose Diamonds & Gemstones\Loose Gemstones\Opal\Black Opals". The seller is "opalobsession" and is located in Nashville, Tennessee. This item can be shipped worldwide.