BBC Antiques Roadshow guest gasps as expert shares whopping value of 'gorgeous' jewellery

WARNING: This article contains spoilers from Antiques Roadshow.

An guest playfully warned an expert to "behave yourself" as she revealed the astonishing value of three treasured family heirlooms.

During a visit to Thirlestane Castle in the Scottish Borders, BBC expert Susan Rumfitt met a guest who showcased two exquisite brooches and a stunning pendant.

When asked about the items' history, the guest explained that the brooches had belonged to her paternal grandmother, while the pendant had been passed down from her maternal grandmother.

Rumfitt pressed the guest to choose her favourite piece, and she confessed a fondness for the pendant, as well as a versatile pearl and diamond piece that could be worn as either a brooch or a pendant.

Focusing on the pendant, the expert began: "So if we start with this one, we've got a beautiful opal and diamond pendant which, if you look on the back, there's actually a little fitting where a brooch could have been put in there as well and even maybe a hair ornament too which would look really, really elegant."

"Date wise, we're looking at around about 1890-1910. We've got two amazing opals in there as well.

"This oval cabochon cut which has a flat back and a domed surface to help intensify the play of colours, the greens, the oranges, the blues.

"Absolutely stunning and to have a fitted box as well is superb, because it's so easy to damage the opals."

Discussing the second piece, she highlighted: "Then of course if we move to this one, it's a lovely pearl and diamond brooch pendant."

"Dates from around 1900s though again, possibly a little bit later, 1900 to 1910 but the period when ladies were wearing beautiful lace fronted dresses."

"It was all about elegance and a lot of the detail in the lace work on the dresses was reflected in the jewellery that was worn as well."

Upon seeing the spectacular pearl and diamond piece, the visitor couldn't help but express admiration, saying, "It is beautiful, it is really lovely", with Rumfitt echoing her sentiment, remarking it was "gorgeous".

She then shifted attention to the second brooch, pointing out its more modern origins: "But again, really well made and you really get a feel for the texture of the leaves there and the beautiful sapphires and diamonds."

Valuation time arrived, and Rumfitt commenced with the latterly discussed 1970s brooch, estimating its worth to be between £500 and £700.

The antique specialist subsequently valued the elegant pearl and diamond brooch pendant at a considerably higher sum of £1,500 to £2,000.

She exclaimed in awe over another piece: "And then, of course, this stunner here, I mean it is absolutely gorgeous, it's got everything going for it."

Her valuation surprised the owner and those present, projecting a potential auction price ranging from £5,000 to £7,000.

The room was filled with astonishment as the guest inadvertently blurted out in disbelief and joy: "No! Behave yourself!"

Rumfitt confirmed with authority that the lowest combined value of the entire assortment would stand at a minimum of £7,500, an announcement that prompted the guest's sincere gratitude.

In a separate interview, the owner expressed her surprise and delight: "[I'm] Absolutely flabbergasted. Delighted to hear such lovely news about the bits of jewellery and no, I won't be getting them remodelled.

"I'll be keeping them the same and I will be wearing them a lot more and enjoying them."

Antiques Roadshow is available to watch on BBC One and BBC iPlayer.