Huge 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 gemstone tester but I recently got a diamond tester and it shows us that it has gemstone hardness! The color on this is so beautiful and deep, it has an absolutely beautiful cut and the size . . .its so BIG for Alexandrite * The color change is pure magic to me, I love the indigo twinkles in natural light! *Comes with certification card, gemstone and snazzy gem box*