Stony-iron meteorites, many times contain about equal proportions of metal and silicate material, and are vary rare (less than 2% of all known meteorites to date). Stony-iron meteorites form within their parent body in places where metal and silicate are mixed.

One type of stony-iron are Pallasites which are rocks composed of a network of iron-nickel metal surrounding a greenish, silicate mineral called olivine. Pallasites probably form when the olivine-rich mantle of an asteroid mixes with the metallic core.

Another type of Stony Iron Meteorite are the Mesosiderites which are mixtures of iron-nickel metal and basalt and probably (theory) formed by the collision of two asteroids.

Pallisites are one of the higest priced as well as most desireable meteorites on the market and can be very exciting for science and you if you are lucky enough to locate a new find! In such a case the value to collectors would be anyones guess and would depend on many factors including classification.

Now as you may have already guessed because of the high iron content both Pallasites and Mesosiderites will sound off quite well with a metal detector, much better than many most Chondrites as a matter of fact and there have been many incredible finds recently here in the USA and abroad that do well to prove this very point!