Certified Color Changing Alexandrite

I went to one of those storage locker auctions and the locker I bought had some wooden boxes that were full of gemstones with certification cards! It was the only auction I've ever been to, now I feel like I should play the lottery but I'm afraid to spoil my luck! All my gems are posted at less than wholesale prices because this isn't what I do for a living, I'm a graphic designer and I have had them forever (since 2014!) I realized that I will never get around to selling them. They've been in a locked closet for YEARS. I know minerals pretty well but I'm not as educated in gems so I don't want to charge a lot when I don't know how to judge value. I've had a lot of these tested, the ones that were tested are mostly the rubies and emeralds and they turned out to be what they said they were. I just don't want to sink more money into testing all of them (It was pricey!) and then try to grade them and get them appraised, and THEN find a buyer to pay a ton for them, it seems so exhausting especially when I get to do my dream job every day! I don't have an expensive gem tester but my diamond tester can show the hardness of a stone AND can tell if a stone is glass or CZ, it won't light up or beeps! The diamond tester and it shows us that it has the right hardness to it for a Alexandrite which is 9 MOHs! The color changes under lamplight and UV light! * Comes with gemstone, certification card & Gem Box *