Some internet auction sites make it hard to find popular items, as many fakes or 'replicas' are put up for sale.
That's why traditional auction houses are thriving - especially if they have embraced the internet.
UK auctioneer Fellows & Sons has a continuous trading history of 131 years in Birmingham, UK.
It employs a series of experts to check items for its auction, including an upcoming antique and modern jewellery auction.
One of the experts who joined them three and a half years ago is Claire Marsh.
She's a gemmologist and jewellery valuer, who works on the eight antique and modern jewellery sales each year (there is the online catalogue for the next sale on Thursday 18th October here: ).
It's Claire's job to ensure the quality of items being sold is high. She said there are 970 lots in the latest sale - and they all have to be checked.
'We get a lot of people bringing some very good items in for us to value' Claire said. 'However we also get some lower quality items as expected.
'You can normally quickly spot something that is of lower quality - for example bought from the internet or a chain store. If not, a closer examination normally reveals what it is.'
Claire has built up her knowledge of antique and modern jewellery with years of practical experience and still gets excited when a good item is first brought in.
She said: 'It's great when you get called down to reception to see and someone has some beautiful Victorian or Edwardian pieces. People inherit items, or they have been stored away for decades. Depending on what they are and the condition they're in, sometimes they can be worth a significant amount of money. I love cataloguing European and old mine cut diamonds as they are less uniform in cut due to past cutting methods. In some ways that gives them more character.'
You can see many of the items valued by Claire at She also values modern jewellery items and enjoys cataloguing new designs and popular gemstones.