Rare Boulder Opal freeform faceted beads (ETB00457) Size:A [5] In today's English citrine

[5] In today's English citrine as a colour is mostly confined to the contexts of (1) gemstones

similar to a geode

dolomite and malachite

It is said to be opaque and unattractive when found in the field

Indian Paint Jasper

Rare Boulder Opal freeform faceted beads (ETB00457) Size:A [5] In today's English citrineAustralian Boulder opals are the second most valuable type of opal (following black opal). Boulder opals are easily distinguished by their layer of solid brown ironstone left on the back of the stone. Boulder opals, as the name suggests, are mined from large ironstone boulders under the ground. Thin veins of colourful opal forms in cracks and fissures in these boulders. Because these veins of colour are so thin, opal cutters need to leave the