No certificate of authenticity and limited warranty card with gemological research association (GRA), because a single moissanite has fewer carats (less than 0.3 carats).
KRE Prime, To care for the 1 Carat Moissanite 925 Sterling Silver Earrings:
Avoid wearing during exercise, as sweat will react with the jewelry to produce silver chloride and copper sulfide, which causes the jewelry to deteriorate and corrode over time.