Black opal (Black and Dark opal or semi-black) - the color of the base material is black, semi-black, dark gray to light gray. Coloring is due to the presence of carbonaceous substances in the molecular structure. It features a number of beautifully opalescent rich colors highlighted with black or dark backgrounds. It is always accompanied by a general opal, the so-called "dots" (the same color as the base mass). black opal is found in layers of clay.
Natural precious opal from Australia (Lightning Ridge) 12,6x6,5x3,8mm, 1,74ct
Natural precious opal from Australia (Lightning Ridge) 9,9x7,6x2,9mm, 1,26ct
Natural precious opal from Australia (Lightning Ridge) 12x7,6x2,6mm, 1,67ct
Natural precious opal from Australia (Lightning Ridge) 6,6x5,8x2,9mm, 0,63ct
Natural precious opal from Australia (Lightning Ridge) 9x5,5x4,7mm, 1,2ct
Natural precious opal from Australia (Lightning Ridge) 10,7x4,8x2,6mm, 0,73ct
Natural precious opal from Australia (Lightning Ridge) 21,8x11x3mm, 4ct
Natural precious opal from Australia (Lightning Ridge) 26,8x9,8x3,7mm, 5,1ct
Natural precious opal from Australia (Lightning Ridge) 22,3x9,8x2mm, 3,3ct
Natural precious opal from Australia (Lightning Ridge) 21,3x6,1x2,6mm, 2,3ct
Natural precious opal from Australia (Lightning Ridge) 15,7x7,5x4,1mm, 3,2ct
Natural precious opal from Australia (Lightning Ridge) 14,7x11,3x2,7mm, 2,77ct
Natural precious opal from Australia (Lightning Ridge) 16,7x11,3x2,2mm, 3,1ct
Natural precious opal from Australia (Lightning Ridge) 17,1x11,8x3mm, 4,1ct
Natural precious opal from Australia (Lightning Ridge) 10x7,2x3,7mm, 1,56ct
Natural precious opal from Australia (Lightning Ridge) 11,5x9,3x3,5mm, 2,27ct
Natural precious opal from Australia (Lightning Ridge) 15,7x9,3x2,7mm, 2,57ct
Natural precious opal from Australia (Lightning Ridge) 20,4x13,3x6,6mm, 10,67ct
Natural precious opal from Australia (Lightning Ridge) 13x9x5mm, 3ct
Natural precious opal from Australia (Lightning Ridge) 20,5x9,6x3,5mm, 4,38ct
Natural precious opal from Australia (Lightning Ridge) 18,8x8,6x2,3mm, 2,65ct
Natural precious opal from Australia (Lightning Ridge) 22,2x16,7x4,7mm, 10ct
Natural precious opal from Australia (Lightning Ridge) 22,2x16,7x4,7mm, 10ct
Natural precious opal from Australia (Lightning Ridge) 31,6x9,1x4mm, 7,41ct
Natural precious opal from Australia (Lightning Ridge) 25,6x17,8x4,3mm, 14,5ct
Natural precious opal from Australia (Lightning Ridge) - 8,3x7,1x2,3mm, 0,76ct
Natural precious opal from Australia (Lightning Ridge) - 7,1x3,9x2,3mm, 0,38ct
Natural precious opal from Australia (Lightning Ridge) - 10,1x5,8x2,7mm, 0,94ct
Natural precious opal from Australia (Lightning Ridge) - 6x5,1x2,1mm, 0,31ct
Natural precious opal from Australia (Lightning Ridge) - 7,6x4,3x2,8mm, 0,62ct
Natural precious opal from Australia (Mintabie) - 26,6x17,6x3,2mm, 9ct
Natural precious opal from Australia (Mintabie) - 26,5x17,8x2,9mm, 8ct
Natural precious opal from Australia (Lightning Ridge)...