Jewellery is a lovely idea. I recently bought my friend a Celtic Cross with a (synthetic) emerald (her birthstone) for her 40th birthday, and had the date engraved on the back. It came to less than €100. This site does Claddagh pendants with birthstones - they're cheaper if you buy the silver version. I didn't buy from the site, but I did go to the shop which is on O'Connell Street in Dublin, and was very happy with my purchase. They did the engraving too.
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