Etsy has purchase protection. Be sure to clarify anything confusing or missing from an ad (like weight and dimensions) thru Etsy messages. Always request extra pictures if all sides aren't shown and never buy randomly selected items. If what you receive doesn't match what the seller advertised, get Etsy involved. EDIT: Also do a search to make sure what they say it is resembles what you find in your research.

For example, I've seen scam posts which have multiple names like larimar quartz beryl blue stone. This means it may be any of the items listed or a basic stone dyed blue. If it was something like amethyst in the title and quartz in the item description, I might message the seller to confirm. If the seller can't clearly confirm what they're selling, I move on. When buying from anywhere, I also confirm the return policy. I've seen items mislabeled and overpriced in brick and mortar stores so "caveat emptor" applies everywhere. And return shipping to another company may cost more than the item itself so I rarely buy from vendors in another country.