_Native Gold of Llano_.—Small flattened grains—reddish: Gold 88.58 8 atoms 88.04 Silver 11.42 1 " 11.96 _Native Gold of Baja_.—Porous: Gold 88.15 8 atoms 88.04 Silver 11.85 1 " 11.96 _Native Gold of Ojas-Anchas_.—Yellowish red plates: Gold 84.5 6 atoms 84.71 Silver 15.5 1 " 15.29 _Native Gold of Trinidad, near Santa Rosa de Osos_.—A solid piece of 50 grains: Gold 82.4 4 atoms 82.14 Silver 17.6 1 " 17.86 _Native Gold of Transylvania (Europe)_.—Pale yellow cubic crystals: Gold 64.52 2 atoms 64.77 Silver 35.48 1 " 35.23 _Native Gold of Santa Rosa de Osos_.—A mass weighing 710 grains: Gold 64.93 2 atoms 64.77 Silver 35.07 1 " 35.23 M. Boussingault has remarked a singlar deficiency in the [p226] specific gravity of the native alloys of gold and silver when compared with calculation, or with the results obtained from an alloy similar in composition prepared by fusion; thus the native gold of Marmato has a specific gravity of 12.666, whereas, by calculation, it ought to be 16.931. The gold of Malpaso, by experiment, is 14.706, by calculation, 18.223, and by fusion, 18.1. The gold of Santa Rosa, by experiment, is 14.149, and by calculation, 16.175. This difference, M. Boussingault says, is not due to porosity in the native gold, as he has observed it in the granular and fine varieties, but a peculiar character of the metal in this state. Such an enormous difference, however, is one that can be admitted only upon repeated experimental proofs, made in the most unexceptionable manner; and, considering that it is only in some of the metals that any permanent difference in specific gravity can be established, and even with them to but a small extent, would be a fact so important as to be worth extreme trouble in the verification.—_Annales de Chimie_, xxxiv. 408.