925 blue gemstone pierced earrings jewelry

Nice, clean, and kept in a clean smoke free home. Blue stone was tested with my presidium II and did register as a gemstone. The device only tests several stones so gemstones land on closes composition. It landed on aqua. I am 100% positive that it’s a gemstone but not certain which stone. I am not a gemologist. My guess would be the aquamarine. Pretty blue stones in a sterling silver frame. Sides are marked 925, brand unknown. Measures 8mm square X 4mm. Backs are marked 925. #pierced-earrings #earrings #jewelry