Value tracker

Hello fellow shiny rock enthusiasts!

I’m new to this world and I was wondering if there are any places that track the value of these gems we all love and adore. Does something like that exist?

For example, trading cards have the Collectr app. Crypto has Coinmarketcap. Precious metals have tickets on the stock exchanges and commodities markets. Is there anything for gems?

I’ve always loved gem stones and I’m trying to get a proper collection going. Not just for investment but simply because I enjoy them and I make my own jewelry from time to time that I give out as gifts and it would help me make better decisions for that hobby.

Thanks in advance for any and all help for a newbie like me!