Coin, a piece of metal converted into money, by the impression of certain marks or figures.

Coin differs from money, as the species from the genus. The latter may consist of any substance, whether metal, wood, leather, glass, horn, paper, fruits, shells; in short, whatever is current as a medium in commerce. The former is a particular specie, always made of metal, and struck according to a certain process, called coining.

The first money in commerce was, doubtless, barter, that is, the exchanging of one commodity for another of equal value; and from the difficulty necessarily attendant on the cutting or dividing of certain commodities, men were first induced to invent a substitute for them, that should serve as a general medium. Such is the origin of coin, which varies in different countries, according to the relative value of the different metals of which specie is composed.

The gold coins current in this country are guineas, half-guineas, and seven-shilling pieces \ those of silver are, crowns, half-crowns, shillings, and sixpences : to these must be added two-penny pieces, pennies, halfpence, and farthings, which are of copper.

Severe punishments are inflicted on those who are guilty of counterfeiting, debasing, or even clipping the current coin of the realm: for the particulars of which, we refer the reader to "Blackstones Commentaries."

A method of taking off casts from coins: - On account of the great value of antique coins, and the difficulty with which they are obtained, few persons have it in their power to procure a complete series. We, therefore, communicate the following mode, by which that desirable object may be attained, and the industrious antiquary enabled to ascertain many disputed points in history.

The method of taking off impressions, by means of plaster of Paris and sulphur, is well known; but, as the former is too soft, and the latter too brittle, they can be preserved only for a short period. This difficulty may be obviated by laying a coat of the finest tin-foil over the medal intended to be taken off, and rubbing it gently with a brush, till it has received a perfect impression, when the edge of it should be pared, so as to render it of the same circumference. The medal should then be reversed, when the tin-foil will fall into a mould ready to receive it, the concave side being uppermost. Plaster of Paris may be poured upon this, in the usual manner; and, when dry, the cast figure should be taken out, with the tin-foil adhering to it; the convex side being uppermost. . In this position, it should be kept in the cabinet; and, if it receive no external injury, will endure for ages.