Free Form Green Opal – Polished Display Specimen Size:Medium 501g–750g Each specimen includes a data

Each specimen includes a data label

and these examples demonstrate the accomplished craftsmanship of their makers

meaning excellent condition with vibrant green colouration

each half of this pair exposes the intricate septa and suture lines that divided the shell into a series of gas-filled chambers — the buoyancy system that allowed the animal to control its depth in the water column

Free Form Green Opal – Polished Display Specimen Size:Medium 501g–750g Each specimen includes a dataA beautifully polished free form specimen of Green Opal, hand cut with a flat base for effortless display. Each piece is graded by weight, so dimensions will vary naturally, and the unique character of each stone in colour, pattern, shape, and finish means no two specimens are alike. Green Opal is a common Opal formed from a silica rich solution of silicon dioxide and water. As water percolates through the earth, it picks up silica from sandstone;