Ct. 100.50 顶级色彩埃塞俄比亚欧泊 - 粗糙系列- 20.1 g

精选自埃塞俄比亚的天然高档未加工欧泊一批，品质优良、具备显著色彩变化效果。
尺寸（长度方向）为 10 到 21 毫米。
所有图片均使用高分辨率相机在干燥的材料上拍摄，并放在不同背景下，以尽量真实地呈现欧泊。
全球发货，挂号邮件并附带跟踪号。
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An opal is a hydrated form of silica with a water content ranging from 3 to 21%.Indeed, it is this permeability to water that makes it a hydrophile.
Opals are deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl, and basalt. Only precious opals show a variable interplay of internal colors.
At microscopic scales, precious opal is composed of silica spheres some 150 to 300 nm in diameter in a hexagonal or cubic close-packed lattice. These ordered silica spheres produce the internal colors by causing the interference and diffraction of light passing through the microstructure of the opal.