Amber (known in mineralogy as succinite) is the mineralised or fossil resin of an extinct pine-tree (probably Pinites succinifer), and though its colour is a transparent pale yellow usually, often it is reddish or brownish, and sometimes tinged with green, blue, or violet; some varieties of amber are almost opaque. It occurs in beds of lignite and in alluvial soils, but it is found in greatest abundance on the shores of the Baltic, between Konigsberg and Memel, where it is thrown up by the sea; its form may be round irregular lumps, grains, or drops. It is hard, rather brittle, and has a perfectly conchoidal fracture, that is, the surface of the fracture has convex elevations and concave depressions. Amber becomes negatively electric by friction, and the power of electrified amber to attract light bodies was known as early as 600 B.C. Its specific gravity varies from 1.05 to 1.07, sometimes reaching 1.1. It is without taste or smell, but when heated by friction or otherwise emits an agreeable odour; it burns with a clear flame and a pleasant smell, leaving about 1 per cent, of ash; it melts at 536° F. It contains from 3 to 8 per cent, of succinic acid; also, it contains two resins - one melting at 29.7 F. and soluble in ether, but not in alcohol; and another resin melting at 221° F. and soluble in alcohol and other bodies.

When its soluble constituents have been dissolved out by means of ether, amber has a similar composition to camphor - C10H160. On distillation, amber yields an empyreumatic oil which is a mixture of hydrocarbons and succinic acid. Sometimes amber encloses Crustacea, centipedes, and insects belonging to species which do not exist now; amber has been found enclosing haves. The most valuable amher is of an opaque lemon colour, and is known as fat amber. An efficient solvent for amber is not known. Amher may be worked in the lathe, the rough amber first being sawn to shape with a bow saw having a fine wire for the blade, tripoli or emery powder being used with it. Whilst the amber runs in the lathe, it may be heated from beneath by a small lamp or a pan of charcoal, as then it softens and is more easily worked; worked cold, it is liable to chip out. On the same principle, when drilling or tapping amber, warm the tool first, and allow it to remain in the amber whilst the latter hardens again; if the tools are made too hot, the amber will be spoilt. By a simple process of polishing amber, it is smoothed with whetstone and water, and then is rubbed with whiting and water, followed by oil applied on a piece of flannel.

When the friction heats and electrifies the amber, lay it aside to cool or it may fly to pieces. Perhaps the more general method of polishing amber is the following. First it is filed to a fairly smooth surface, which is improved by rubbing with Trent sand and water or with scraped Flanders brick and water applied with a flannel. Rottenstone and oil are then rubbed on with a flannel, followed by dry rottenstone applied with the palm of the hand. Amber turned in the lathe is smoothed with glasspaper, and polished with rottenstone and oil. The lapidary polishes amber first on an iron lap with diamond dust and oil of brick; then on a lead lap with coarse emery and water, followed by fine emery and water; then with flour emery and water on a mahogany lap; then on a list mill with pumice powder and water; and finally on a leather lap or piece of buff leather with fine putty powder and water. Sometimes moist putty powder applied by the palm of the hand follows the leather lap. Amber that is to be polished with facets is treated on pewter laps with crocus. Except that the amber is held in the unaided fingers, the process resembles the cutting and polishing of gems.

Amber may be tested by (1) warming it slightly; artificial amber will then smell of camphor. (2) Holding a small chip in a flame, when amber melts and burns slowly, whilst most artificial amber burns vigorously. (3) By weighing. The real is not so heavy as the artificial substance. To distinguish amber from fossil copal, heat a particle and hold a piece of moistened lead acetate test paper in the fumes. If it is amber, the paper will be blackened; if copal, the paper will not be discoloured.