SGF Solid 10K Yellow Gold Oval Cut Blue Topaz Ring with Sapphire Halo - Size 7

SGF solid 10K yellow gold ring set with an oval blue topaz framed by a halo of round white sapphires, marked 10K, SGF and THAILAND. The center stone is a clean oval in the bright sky blue that topaz is known for, held in prongs with the gallery left open beneath so light enters from the sides and the back rather than only from above. Around it the white sapphires are prong set in a radiating arrangement that widens toward the shoulders, so the head reads as an elongated diamond shape on the hand rather than a plain circle.

Pairing blue topaz with white sapphire rather than a softer accent stone is the choice that makes this piece work. White sapphire is corundum, the same mineral as ruby, and it sits at 9 on the Mohs scale, so the halo returns light with a hard bright flash instead of a milky glow. Against that brightness the topaz reads deeper and more saturated than it would surrounded by anything duller. The THAILAND stamp places manufacture in one of the world's primary centers for colored stone cutting and setting.

Size 7. The head sits up off the finger with real presence, and the shoulders taper down into a slim band so the ring reads as a statement without the whole shank being heavy.

Verifications:
Solid 10K gold has been verified using an Auracle Gold Analyzer.
White sapphire and blue topaz have been verified using a Presidium Gem Tester II.

Details:
Maker's Mark: SGF
Metal: Solid 10K Yellow Gold
Origin: Thailand
Hallmarks: 10K, SGF, THAILAND
Center Stone: Blue Topaz
Center Stone Cut: Oval
Center Stone Setting: Prong
Halo Stones: White Sapphire
Halo Stone Count: 12
Halo Setting: Prong
Ring Size: 7
Condition: Excellent estate condition

Fun Facts:
Natural blue topaz is one of the rarest colors the mineral produces, which is why effectively every blue topaz on the market began life colorless. The color is created by bombarding clear topaz with radiation to knock atoms out of position in the crystal lattice, then heating it to settle the result. Those displaced atoms are what absorb light in the yellow range and leave blue behind. The color is locked into the structure itself rather than sitting on the surface, so it does not fade, rub off or wash out.
White sapphire is not a lesser cousin of blue sapphire, it is the same stone with nothing added. All sapphire and all ruby are corundum, aluminum oxide, and the entire difference is trace elements. Chromium produces red and the stone is called ruby. Iron and titanium produce blue. With no trace elements at all the crystal grows colorless. At 9 on the Mohs hardness scale corundum is second only to diamond, which means a white sapphire halo holds its polish and its edges far longer than most colorless accent stones.