This is a strange vintage Sterling Silver brooch.
It is certainly a long length - being about 9 cm in length.
It is not hallmarked but dates to the 20th century. It is silver and marked Sterling on the back, as photographed.
It does not have a modern catch - but an older c-scroll one. This style of bar brooch was more popular in the 1940s and 1950s - so that is the probably date of this piece.
There are polished square red cabouchons at each end of the bar - these are inset to a silver setting with four claws. Beside the agates on each end of the bar are decorative art nouveau-style leaf motifs. These are nicely made with fine decoration to them.
This would probably look nice pinned onto a wide black scarf or a lapel. Listed at a very fair price for this unusual old brooch.
UK Postage will be £2.95 and this will be applied to your order at the checkout.