Platinum, Sphene & Diamond Ring 2.98ctw, 9.3 Grams Gemstone Natural Jewelry Diamonds
Lot #454
Current Bid
$1,000
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Description
size: 6 weight: 9.3 grams material: platinum gemstone: natural sphene: 2.62ct diamonds: 0.36ctw, VS clarity, G-H color Notes from the Curator Sphene—the gem trade name for the mineral titanite—occupies a quiet but singular place in the world of colored stones, prized almost exclusively by collectors for a dispersion of 0.051, higher than diamond's 0.044. This means sphene splits light into spectral colors more effectively than diamond, producing vivid rainbow flashes. The 2.62-carat cushion-cut stone at the center of this platinum ring shows the warm olive-to-yellow-green tonality typical of specimens from Madagascar or Sri Lanka; titanite has a resinous to adamantine luster that is rarely seen in other minerals, giving the facets a glassy, almost liquid sheen even before the light breaks into fire. The name derives from the Greek *sphenos*, wedge, after the sharply angled monoclinic crystals in which the mineral grows; platinum has long been the metal of choice for sphene, its neutral tone allowing the stone's chromatic play to dominate. Sphene is pleochroic and has high dispersion, though it may not show both properties at the same time, and the elongated cushion cut here maximizes the fire visible through the table.
Bidding Details
- Starting Bid: $1,000
- Buyer's Premium: 20%
- Auction End Date: August 31, 2026
Bid Increment Schedule
The minimum amount your bid must exceed the current price, based on the current bid level.
| Current Price | Minimum Increment |
|---|---|
| $0 – $24.99 | $1 |
| $25 – $74.99 | $2 |
| $75 – $149.99 | $5 |
| $150 – $499.99 | $10 |
| $500 – $999.99 | $25 |
| $1,000 – $4,999.99 | $50 |
| $5,000 – $9,999.99 | $100 |
| $10,000 – $24,999.99 | $250 |
| $25,000 – $49,999.99 | $500 |
| $50,000 – $99,999.99 | $1,000 |
| $100,000 – $499,999.99 | $2,000 |
| $500,000+ | $5,000 |
