
Some opals from Spencer, Idaho show asterism or the “star stone” effect. Learn how to price these beautiful but rare star opals.
2 Minute Read

I love working with opal from Spencer, Idaho. On rare occasions, I turn up a star stone. I know star opals are very rare. So as you can imagine, I'm having a heck of a time trying to put a realistic value on what I cut. Does anyone have any pricing information or guidelines for star opals?
I've cut both star opals and cat's eye triplets from Spencer material. They are indeed rare and very beautiful. I would suggest contacting gem shops from the area. They might be able to give you the information you need or put you in touch with local cutters who know the market.
This reference may be old but it might help. Back in the mid-1970s, Lapidary Journal (now Lapidary Journal Jewelry Artist) did a cover story on star opals from Spencer. Check their index or try to find a copy online or at a library. The story and photos may give you a better idea of what to take into consideration when judging quality. The article also explains the cause of this rare phenomenon.
Rick Martin, Martin Designs

Pricing and appraising opals is already a complex art. Pricing star opals is more difficult than you might think. This stone is so rare few people sell it.
Here are some suggestions:
This is what gemologists do when they grade a rare stone. However, the price is ultimately dictated by what you want for it and what the buyer is willing to pay.
Douglas LeGrand, GG
Editor's Note: Check out these pics of star opals. For a look at a doublet made from a star opal from Spencer, Idaho, click here.










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I love working with opal from Spencer, Idaho. On rare occasions, I turn up a star stone. I know star opals are very rare. So as you can imagine, I'm having a heck of a time trying to put a realistic value on what I cut. Does anyone have any pricing information or guidelines for star opals?
I've cut both star opals and cat's eye triplets from Spencer material. They are indeed rare and very beautiful. I would suggest contacting gem shops from the area. They might be able to give you the information you need or put you in touch with local cutters who know the market.
This reference may be old but it might help. Back in the mid-1970s, Lapidary Journal (now Lapidary Journal Jewelry Artist) did a cover story on star opals from Spencer. Check their index or try to find a copy online or at a library. The story and photos may give you a better idea of what to take into consideration when judging quality. The article also explains the cause of this rare phenomenon.
Rick Martin, Martin Designs

Pricing and appraising opals is already a complex art. Pricing star opals is more difficult than you might think. This stone is so rare few people sell it.
Here are some suggestions:
This is what gemologists do when they grade a rare stone. However, the price is ultimately dictated by what you want for it and what the buyer is willing to pay.
Douglas LeGrand, GG
Editor's Note: Check out these pics of star opals. For a look at a doublet made from a star opal from Spencer, Idaho, click here.
