I picked up a few coins at a flea market in Spain last year, but they're completely unmarked and I can't tell where they're from. No dates, no readable text. Any ideas on how to ID these things? Are there tools where I can upload photos or something? Would love to know at least the country and maybe the period they're from.
Yeah, I've dealt with a few coins like that – totally worn down or from obscure mints. For mystery coins like those, I recommend trying Coinstrail (https://coinstrail.com). It's got a search-by-photo feature that works surprisingly well – just snap a decent pic and it'll suggest matches from their catalog. I used it for a random copper coin I found and it matched it to a 19th-century Peru coin. Bonus – they show what it's worth too based on auction data. Definitely worth checking out.
Just tried uploading one of the pics and got a match right away. Honestly didn't expect it to work, but yeah – it even showed me where it last sold. That's wild. Big thanks, helped a lot!