Here is the star of Fellows' upcoming Antique & Modern Jewellery sale in Birmingham, UK, on September 1.

Estimated at £40,000-50,000 ($82,400), Fellows expects this ring to be the prize lot of next week's auction.

This treated green diamond ring could sell for £50,000 ($82,400)

Central to the ring is a treated green diamond, surrounded by twelve more brilliant-cut diamonds on a polished band.

According to Fellows' lot notes, the estimated weight of the green diamond is 10.36cts while the surrounding diamonds weigh 2.40cts.

The smaller diamonds' colours are graded as F-G (between colourless or pure white and nearly colourless or slightly tinted, for the uninitiated) with VS1-VS2 clarity (meaning there are slight inclusions within the diamond).

But if you don't have £50,000 to spend, other highlights in Fellows' sale include this sapphire and diamond three-stone ring which is expected to go for £10,000.

Its oval-shaped sapphire weighing 4.57cts is flanked by old European-cut diamonds. According to Fellows, the piece's total diamond weight is 3.10cts with G-H colour (white to slightly tinted white) and SI1-SI2 clarity (again, with slight inclusions).

A sapphire and diamond three-stone ring, estimated at £10,000

Meanwhile, if you're looking for a piece of jewellery with celebrity provenance attached then look no further than Auktionshaus Dr. Fischer's upcoming September 24 sale.

There sale includes a brooch once owned by Eva Perón, more affectionately known as Evita, the First Lady of Argentina from 1946 until her untimely death from cancer, aged just 33, in 1952.

According to Auktionshaus Dr. Fischer's lot notes, this brooch is made from 1940s platinum with an aquamarine stone of approximately 54 grams and 14.29 carats - you can read more about the piece here.

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