Overview
The '15CT' stamp confirms the British 15-karat gold standard used between 1854 and 1932, strongly supporting the late Victorian/Edwardian dating alongside the delicate scalloped openwork design and milgrain bezel setting.
Identification
Photo reference
5 uploaded photos
Overview
The '15CT' stamp confirms the British 15-karat gold standard used between 1854 and 1932, strongly supporting the late Victorian/Edwardian dating alongside the delicate scalloped openwork design and milgrain bezel setting.
Story
The brooch is presented in a fitted box from Gibson & Co. Ltd of Belfast, a notable jeweler and silversmith that held a Royal Warrant. While the brooch itself lacks a specific maker's mark—common for pieces retailed by prominent jewelers of the era—the '15CT' stamp confirms British Empire origins between 1854 and 1932, perfectly aligning with the Edwardian aesthetic. The secondary market for Edwardian and late Victorian 15ct gold jewelry remains stable, driven by collectors of period-specific pieces.
Maker / Origin
Unmarked (Retailed by Gibson & Co. Ltd, Belfast)
Condition & Value
Visually, the brooch presents well with a vibrant opal and intact scalloped gold work. The original Gibson & Co. box appears in good period condition, which enhances the overall presentation.
Full Research
Sold comps, value drivers, and venue guidance pulled from recent auction results.
The secondary market for Edwardian and late Victorian 15ct gold jewelry remains stable, driven by collectors of period-specific pieces. Bar brooches, while less universally worn today than in the early 20th century, maintain consistent demand when featuring vibrant, undamaged colored gemstones like opals. Original fitted presentation boxes from known retailers add a distinct premium, appealing to purists and historical collectors.
▲ Confirmed '15CT' stamp establishes British late Victorian/Edwardian gold purity.
▲ Original fitted presentation box from Royal Warrant holder Gibson & Co. Ltd adds a historical premium.
▲ Solid opal displays vibrant play-of-color in the provided imagery.
▼ Unverified opal condition — edge chips or crazing would drop the value to the $70 damaged-stone floor.
▼ Missing total weight and dimensions prevents precise intrinsic gold value calculation.
▼ Unverified clasp mechanism — period-correct C-clasps or early safety catches are required to confirm an unaltered state.
Best Venue
Pending confirmation of the opal's condition and the gold weight, this piece is best suited for a specialized antique jewelry auction. Ensure the original Gibson & Co. box is prominently featured in all photography, as it provides crucial period context. If the opal is confirmed flawless and the weight is substantial, consider setting a reserve near the $250 mark.
Upside Potential
If the total weight exceeds 5 grams and the opal is confirmed to be completely free of crazing or chips under magnification, the piece could push toward the $800+ retail asking tier seen in the 1stDibs and Jewellery Warehouse comparables.
Also found — market-range context
Surfaced during research but not used to anchor the valuation — wrong form, species, era, or no published price. Shown so the market range around this item is visible.