Antique Australian 18ct Yellow Gold Boulder Opal Brooch Circa 1890

Please note boxes are for display only unless otherwise stated


Outstanding Australian 18ct yellow gold brooch centring a large oval en cabochon boulder Opal weighing 37.2cts and measures 33.5mm x 23mm.

Crafted around the 1890’s from 18ct gold which has been **’bloomed’ to display an even higher carat finish resembling 22ct gold.

The Opal is bezel set to the then fine and intricate cannetille border.
To the rear there is a photo locket which sadly has lost its cover over the years however our jeweller had replaced this with a thick plastic and it can be used for a photo if desired.

Retaining its original C clasp and pin and safety chain this wonderful piece of Australian history can also be worn as a pendant simply by threading a chain through the closed pin or can be attached to a lobster clasp on your favourite guard chain. (See photos).

Impressively heavy and solid at 21.5 grams with outstanding workmanship this early Australian piece would be as asset to any collection.

What is Blooming?

Blooming, a popular finishing technique for karat gold jewellery from 1870 to 1890, was first documented in 1853. The means for creating a bloom finish involved dipping a gold item into a boiling mixture of hydrochloric acid (muriatic acid), saltpeter (potassium nitrate), salt and water. This process burned off any alloys on the surface resulting in an alloy-free, thin layer of soft, pure gold on the item.

Boulder Opal 37.2cts - 33.5mm x 23mm

4.73cm x 3.7cm

 21.5 Grams

Tested as 18ct gold

Very very good antique condition.  Natural inclusions to Opal, no chips or cracks.  Gold is bright and lovely.  Minor marks to gold at rear, nothing significant.  C clasp and pin original with no repairs.  Outstanding piece. 


Laybys available on all items $400 and over. Contact us for more details.

All our items are antique or vintage unless otherwise stated. Condition will be described, it is the responsibility of the buyer to read descriptions and view photos.  Please refer to our guide Caring For Antique & Vintage Jewellery for more details. 

Prior to purchase, please view our Purchase Guide & Return Policy. All purchases within Australia will be sent via express post as a complimentary service.  International rates apply.  Please view our Shipping & Delivery Policy for more details

Please note: Any duties imposed by countries for importing our items are the buyers responsibility

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