That means the opal ring has its own individual shape instead of the oval or circle or pear shape in which the black and white opals are usually cut.
The free form layout will not look like any other shape you notice but will still be fun. Another major difference is that boulder opal is usually not smooth and top notch. We call this a cabochon from an old French word that translates into the English word hat. Cut many opals into cabochons because they enhance their color features by allowing light to enter and exit the stone for maximum effect.
Boulder opal will usually have a fixed bed of opal sitting on a bed or a dark brown stone. This means that the stone will need the craftsman to make a special stone setting because the ready-made or molded settings usually come in oval cuts made of stone cabochon cuts and not free-form stones.
There are two subtypes of stone opal: seam and matrix. Seam opal is found when opal material attacks cracks in ironstone rock. When the metal is broken by running the tractor across or hitting it with a large hammer the rock will split into two parts. Opal will be in each section.
Matrix opal is where opal works randomly across the rock. So a real stone is cut and polished with an opal matrix inside it. Make beautiful opal pendants.
Boulder opal is heavier than black opal or white opal because it usually has a metal stone so it makes it very difficult to make other types of opal jewelry such as opal rings or opal earrings. It is certainly not possible to do anything but with hanging paints it is fine and makes great opal curtains.
No comments:
Post a Comment