This is a listing for a "pendant top" stamped with "925". As you can see in the image, a "stone" is embedded in the center. Of course, it's not an expensive "gold base" or "platinum base," but rather embedded in a much cheaper "silver base," so it's unlikely to be an expensive diamond. Also, from that fact, I'm guessing it's probably "zirconia," or something like that. I am not an expert on this item, and I have no product knowledge, I apologize. However, I have been involved with materials for a certain amount of time, so I can guarantee the silver fineness of 925. Of course, that's because I've measured the "specific gravity," and the result of that specific gravity measurement was "10.03." (The weight of the body was 10.63g, and the weight in water was 1.06g) This value indicates a silver fineness of around 700 per mille (‰). However, what we must not forget here is that it includes a "stone." Naturally, since I'm measuring with a "stone" that has a much smaller specific gravity than silver, the specific gravity will be much, much smaller. Of course, if I remove the stone and measure it, the specific gravity of silver 925 will be around "10.36." Also, if it were a pendant top made of other metals (excluding gold, platinum group metals, palladium, and lead), it is absolutely impossible for the specific gravity to be more than "8.96" with the stone attached. This is because, other than "gold," "platinum group metals," "palladium," and "lead," no matter what alloy (iron, nickel, copper, zinc, tin) it is, the specific gravity will not exceed 8.96. Therefore, the fact that it exceeds 8.96 with the stone attached means that this item is "definitely a silver alloy," and of course, I guarantee it is 925. Please purchase with confidence. Regarding the condition, it has become black due to sulfidation, and there are many small scratches and scuffs, and it is by no means a clean item, so please be aware of this. If you are looking for one, how about it? Size Maximum length: 52 mm (including the bale) Weight: 10.63g Marking: 925 (guaranteed)