Iron Meteorites

Iron meteorites are the exposed cores of ancient asteroids — dense, metallic objects that formed when small planetary bodies melted, differentiated, and were later shattered by collisions. Every iron meteorite in this collection is a direct sample of an asteroid's interior, typically 4.5 billion years old. Unless specifically stated in the listing, each is authenticated through Meteoritical Bulletin classification.

What makes iron meteorites distinctive

Iron meteorites are composed primarily of iron-nickel alloy — the minerals kamacite and taenite — and are immediately recognizable by their metallic weight and density. Most contain enough metal to attract a strong magnet. When cut, polished, and etched with dilute acid, the majority reveal the Widmanstätten pattern: an interlocking geometric crystal structure of kamacite and taenite bands that formed over millions of years of slow cooling deep inside an asteroid. This pattern is impossible to replicate artificially and is diagnostic of genuine iron meteorite origin.

The bandwidth of the Widmanstätten pattern reflects cooling rate: fine octahedrites cooled faster in smaller or shallower bodies; coarse octahedrites cooled more slowly at depth. Each specimen's internal structure is a direct record of its parent asteroid's thermal history.

Classification

Iron meteorites are classified into chemical groups — IAB, IIIAB, IVA, IVB, and others — based on trace element ratios measured by neutron activation analysis. Each group represents a distinct parent body or family of parent bodies. Structurally, they are divided into octahedrites (displaying the Widmanstätten pattern), hexahedrites (low nickel, showing Neumann lines rather than Widmanstätten), and ataxites (very high nickel, no visible pattern). Every specimen in this collection carries a Meteoritical Bulletin classification with a direct citation.

Collecting iron meteorites

Iron meteorites are among the most durable and display-ready specimens available. Common forms include etched slices showing the full Widmanstätten pattern, polished slices highlighting metallic luster, complete individuals preserving natural regmaglypts and fusion crust, and end cuts combining exterior and interior features. Proper storage with desiccant is important — iron meteorites are susceptible to oxidation in humid environments. See our guide: How to Care For and Store a Meteorite.

Frequently asked questions

Are all iron meteorites magnetic? Yes — iron meteorites are strongly ferromagnetic due to their iron-nickel composition. They will firmly attract a strong neodymium magnet.

What is the Widmanstätten pattern? It is an interlocking crystal structure of kamacite and taenite that forms only during millions of years of slow cooling inside an asteroid. It cannot be faked and is definitive proof of iron meteorite origin. Read more: Widmanstätten Pattern Explained.

Do iron meteorites rust? Yes — metallic iron oxidizes when exposed to moisture. Store with silica gel desiccant. Etched specimens benefit from a thin lacquer coating. Read more: Do Meteorites Rust?

Are these specimens authenticated? Unless specifically stated in the listing title or description, specimens in this collection are Meteoritical Bulletin classified with a direct link to the official record. Every purchase ships with a Treasure Coast Meteorite Co. certificate of authenticity.

See also: Stony-Iron Meteorites · Stony Meteorites · Widmanstätten Pattern Explained · Types of Meteorites