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Gold-leaf Alloys.
Оглавление—All gold made into leaf is more or less alloyed. The gold used by the goldbeater is alloyed according to the variety of color required. Fine gold is commonly supposed to be incapable of being reduced to thin leaves. This, however, is not the case, although its use for ordinary purposes is undesirable on account of its greater cost. It also adheres by contact of one leaf with another, thus causing spoiled material and wasted labor; but for work exposed to the weather it is much preferable, as it is more durable and does not tarnish or change color.
The following is a list of the principal classes of leaf recognized and ordinarily prepared by beaters with the proportion of alloy they contain:
| Gold grs. | Silver grs. | Copper grs. | ||
|---|---|---|---|---|
| I. | Red gold | 456–460 | — | 20–24 |
| II. | Pale red | 464 | — | 16 |
| III. | Extra deep | 456 | 12 | 12 |
| IV. | Deep | 444 | 24 | 12 |
| V. | Citron | 440 | 30 | 10 |
| VI. | Yellow | 408 | 72 | — |
| VII. | Pale yellow | 384 | 96 | — |
| VIII. | Lemon | 360 | 120 | — |
| IX. | Green or pale | 312 | 168 | — |
| X. | White | 240 | 240 | — |
