This is a fossilized partial Megalodon tooth. These teeth are highly sought after by collectors due to the shark's massive size and prehistoric existence. Even fragments can hold value, offering insights into the diet and environment of this extinct apex predator. Market value varies based on size, completeness, and condition, with larger, more complete teeth fetching higher prices. It measures 2 1/2 inches in length. Thanks for looking and please message me for questions.