In late 2018, I had the opportunity to spend some time onsite with jewelry store retailers and learn more about what they want and need in retail point of sale systems. Note that these are stores that are not associated with any sort of chain or franchise (but my advice would be the same regardless).
Jewelry retailers generally deal with products that may never be sold again but also have complex descriptions and sizing/design requirements. Many of you also have on premise repair services so tracking work orders is important. Financing options for you customers is important as well but appears to be handled by a third party and is not part of the POS system functionality.
You also track detailed information about your customers so you can market to them at set time intervals.
I've not had any personal experience with jewelry store specific POS programs but general POS programs that work well for jewelry stores would be NCR CounterPoint, Retail Pro, and Retail Management Hero on the "buy it and own it" side of things.
For subscription based point of sale programs, look at NetSuite, LightSpeed, Microsoft Dynamics 365/AX and Cloud Retailer.
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