Figuring out uncooked opal is an important step in assessing its high quality and worth. Opal is a hydrated silica mineral that displays a novel play-of-color, or iridescence, when seen from completely different angles. This phenomenon is attributable to the diffraction of sunshine inside the opal’s inside construction. Uncooked opal is usually discovered within the type of nodules or lots, and it could actually differ in coloration from white to black. Probably the most worthwhile opals are people who exhibit a vivid and intense play-of-color.
There are just a few key traits that may enable you to to establish uncooked opal. First, opal is a comparatively tender mineral, with a hardness of 5.5 to six.5 on the Mohs scale. Which means that it may be simply scratched with a knife or different sharp object. Second, opal is a translucent to opaque mineral, which means that it permits some mild to move by it, however it isn’t fully clear. Third, opal has a conchoidal fracture, which means that it breaks with a curved, shell-like floor.
