What Is Amber? It's Not a Mineral — It's Fossilized Tree Resin

Amber isn't a mineral — it's an organic material, fossilized resin from ancient trees (mainly conifers), which distinguishes it fundamentally from every crystal covered elsewhere in this encyclopedia.

How It Forms

Amber forms when tree resin, exuded as a sticky protective substance (often in response to injury or infection), is buried and subjected to heat and pressure over an extremely long timescale — generally millions of years — during which the resin's organic compounds polymerize and harden into the stable, fossilized material we call amber. Most commercial amber is tens of millions of years old; some Baltic amber is estimated at around 44 million years.

Trapped Ancient Life

Because it started as a sticky liquid, amber can trap and preserve insects, plant fragments, and other small organisms that got stuck in the resin before it hardened — these inclusions are exceptionally well-preserved, sometimes down to fine anatomical detail, giving paleontologists a genuinely unique window into ancient ecosystems that wouldn't survive in ordinary fossilization. This phenomenon is real, though the idea of extracting usable ancient DNA from amber-trapped insects (as in popular fiction) isn't something scientifically demonstrated to work in practice.

Amber vs. Copal

Copal is a similar-looking resin that hasn't fully fossilized — generally under a few million years old and chemically less stable than true amber. It's sometimes sold as amber, whether through genuine confusion or deliberate misrepresentation. Simple tests can help distinguish them: a hot needle touched to the surface produces a resinous, slightly sweet smell and softens copal more readily than true amber; a saltwater solution (roughly 1 part salt to 2 parts water) will float genuine amber, while denser plastic imitations typically sink.

Where It's Found

The Baltic region (particularly around the Baltic Sea coast) is the most significant global source, supplying the majority of amber used in jewelry historically and today; Dominican amber is notable for a higher rate of well-preserved insect inclusions.

Quick Facts

Not a mineral — fossilized organic tree resin — Hardness: 2–2.5 on the Mohs scale (soft) — Can contain genuine ancient insect/plant inclusions — Distinct from younger, less stable copal — Major source: the Baltic region.