Thanks for your question. I hope I can help.
Under contract law terms the parties need to be aware of the terms at the point the contract is made. Generally the contract is made on payment, in this case the deposit. Now the jeweller should communicate to you prior to payment that the deposit was non refundable before you paid it. The fact it is stated on the till receipt is an attempt to incorporate a term in to the contract after it was made. Any attempt to incorporate a term after formation of the contract will render that term void.
You should be entitled to the return if the deposit.
Did you pay the deposit by credit card? You could speak to the credit card company about it to see if they can assist. If not then you will have to sue via moneyclaimonline.com to recover the deposit.
I hope this assists you.
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