This is a standard 10 lb. mushroom anchor, generally used to secure small dinghys.   I've had it for about 15 years, but used it for only a few of those years.

   It appears to be identical to Seachoice model 41220 ( Defender catalog p49).

   As photos show, it does have areas of rust, which is perfectly normal after some of the original coating is lost.  But there is no significant loss of weight, so will still work Aok.

   Anchor is 8" in diameter & about 7-3/4" high.