Amber, Copal or Plastic: Clues So You Do Not Get It Wrong

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What is called amber, copal, resin

Amber is tree resin, hardened and transformed over tens of millions of years, under the heat and pressure of sediments. It is not a mineral but an organic polymer made from compounds derived from resin. It is soft (2 to 2.5 on the Mohs scale), light (density 1.06 to 1.10), and it can trap insects, plants or air bubbles. This state is reached only at the end of a long transformation: the resin first becomes copal, and then amber.

Several origins coexist on the market:

• Baltic amber (succinite): the best known in Europe, mined mainly in the Kaliningrad region (which, according to Wikipedia, holds about 90% of the exploitable reserves), but also in Poland and Lithuania;
• Dominican amber: younger, often very clear, sometimes blue under daylight fluorescence;
• Burmese amber (burmite): the only Cretaceous amber mined commercially (about 99 million years old), prized for its inclusions; mining takes place in a conflict region, and a learned society of palaeontologists has called for caution regarding it (see below);
• copal (Colombia, Madagascar, East Africa): sub-fossil resin, much younger.

In jewellery, the name “amber” is used for genuine fossil resin; copal, plastic or glass are not amber.

The table of signs

Criterion	Amber	Copal	Plastic or glass
Age	Tens of millions of years	A few thousand to a few million years	Recently made
Weight in the hand	Very light, warm to the touch	Very light	Plastic: light or heavier depending on the type; glass: heavy and cold
Very salty water	Floats	Floats too	Many plastics sink; polystyrene floats; glass sinks
Surface	May have a weathering crust, resinous lustre	Surface that cracks over time, looks “fresher”	Greasy or overly perfect lustre; a moulding line may be visible
Inclusions	Insects, plant debris, irregular bubbles; “water lily leaves” in heated amber	Modern or recent insects, often well preserved	Insects sometimes added, round and aligned bubbles
Smell when gently rubbed	Slight smell of pine resin	Stronger resin smell	No resin smell, sometimes a chemical smell
Static electricity	Rubbed on cloth, attracts small pieces of paper	Same	Some plastics do this too: weak clue

The table shows one essential point: none of these signs reliably separates amber from copal. Copal also floats in very salty water, and the tests that distinguish them best (solvents, heat) damage the piece.

Simple, safe tests

1. Read the description. Origin (Baltic, Dominican, Burmese), nature (natural amber, pressed, copal), treatment (heated, dyed). The absence of information is a reason to ask.
2. Observe under a loupe. Irregular bubbles, flecks of mica or plant matter are natural. Perfectly round or aligned bubbles suggest plastic. Small circular cracks like “water lily leaves” come from heating and indicate lightened amber.
3. Float the piece in salt water. Pour lukewarm water into a glass, add cooking salt until it no longer dissolves (about a quarter salt by weight). Choose a piece with no metal mount or glue, and lower it gently: amber floats. This rules out glass and many plastics, but not copal or certain light plastics. Rinse and dry afterwards.
4. Rub the piece on wool cloth and bring small pieces of paper close: it attracts them. The test proves little, as plastics can also become charged.
5. Weigh and touch. Amber is light, warm to the touch, and does not feel as cold as glass.

Avoid. It is sometimes advised to prick the piece with a white-hot needle (amber gives off a smell of pine, plastic a chemical smell) or to apply acetone or ethanol (copal becomes sticky). These tests leave a mark, give off irritating fumes and use flammable products: we advise against them. The same goes for flame and acid.

What these tests cannot prove. They do not distinguish amber from copal, and they do not detect pressed or clarified amber. For a valuable piece (with an insect, or a large size), ask for a laboratory certificate (infrared analysis).

Pressed, heated, dyed: the common treatments

Amber is often heated to lighten it: the result is a clearer piece, sometimes with circular cracks. Small fragments are compressed under heat to make pressed amber (ambroid or “reconstituted amber”). It is sometimes dyed (cherry, green) or glued onto a backing. These practices are old and the material remains amber, but the seller must disclose them. In France, decree no. 2002-65 of 14 January 2002 also covers organic materials of plant or animal origin: the description must remain fair, so pressed, dyed or imitation amber must not be presented as raw natural amber.

Inclusions deserve particular attention: real insects do exist in Baltic or Dominican amber, but modern insects are sometimes trapped in copal or resin; a state of preservation that is too perfect, with every leg and colour intact, should raise an alarm. A large insect in an inexpensive piece is rarely authentic.

Safety, children and ethics

• Teething necklaces. Amber necklaces sold for babies have no proven effectiveness against teething pain, and they present strangulation and choking risks. We do not recommend having a child wear one. Ask a paediatrician or a pharmacist for advice.
• Never put amber in the mouth. It is flammable and gives off smoke when burnt: keep it away from any flame (see the incense guide for safety).
• Burmese amber. Part of the extraction takes place in a conflict region. In 2020, the Society of Vertebrate Paleontology recommended that journals stop publishing research on Burmese specimens acquired after June 2017, then hardened its position in 2021. This is not a ban on sales, but a reason to ask about the origin and the chain of supply.

As for care: amber is soft and dislikes solvents, perfumes, household products, heat and prolonged sunlight. Clean it with a soft cloth and lukewarm water. See the Mohs scale.

The right questions to ask before buying

• Natural amber, pressed, heated, dyed, or copal?
• What origin is stated (Baltic, Dominican Republic, Burma)?
• Is the piece set in a mount or made entirely of one block?
• For an inclusion: is the insect identified (species, age)? Is a certificate provided?
• Does the photo show the exact piece? Shades of honey and cognac vary greatly from one piece to another.

See also the amber profile, “Recognising real amber” and how to read a label. Our product pages commit to naming materials accurately: our commitments.

Frequently asked questions

Also read

The meanings mentioned belong to tradition and symbolism. They are neither promises of results nor medical advice. Back to Recognizing real stones.