298 LIVERSIDGE: PRESENCE OF GOLD IN NATURAL SALINE, ETC. XXV.-Presence of Gold in Natural Saline Deposits and Hayine Pluiz ts. BY A. LIVERSIDGE, LL.D., F.R.S., Professor of Chemistry in the University of Sydney. THE experiments referred to in this paper were made in 1895 in connection with an investigation into the presence of gold and silver in sea water *; but as the work has had to be laid aside for a time, the present paper may be regarded as a preliminary one. Amongst the substances already examined for gold are rock salt, sylvine, and other similar mineral substances, also bittern, the ashes of seaweeds, kelp, oyster shells, &c., all of which were found to contain both gold and silver ; the amounts of silver will be given in a subsequent paper. The process used for determining the amount of gold was to dissolve from 100 to 1000 grams of the salt in water, then to add, without previous filtration (since the gold may be wholly or in part i n suspen- sion), from 0.5 to 5.0 grams of ferrous sulphate, and allow the latter to oxidise slowly by exposure to the air or by drawing air through the mixture; the precipitate produced was then scorified with lead free from gold, and cupelled, or, to hasten the experiments, the iron hy- droxides were precipitated by the addition of a little ammonia.This process, as shown in one of the previous papers above referred to, does not throw down all the gold, so that the results are understated : later on, I hope to repeat the determinations by other and more efficient processes. My principal reason for examining the saline minerals was because gold occurs insea water, and it is not unnatural to expect its presence in salts deposited from sea and other waters ; further, as I had found that fungoid growths removed gold from suspension and from solution,? I thought that seaweeds and other marine organisms might show an accumulation of gold.This I found to be the case. Amongst the results are the following. Rock Salt, Cheshire 1.7 grains of gold per ton, ,? 9 , red ,> 1.49 ,, 9 ) 9 7 ,, ,, ,, Stassfurth 2.03 ,, 9 , ,? Table Salt . . . . none ,, 7, 9 7 * (1) ‘‘ On the Amount of Gold and Silver in Sen Water.” Jozmn. Boy.. Soc. (2) “011 the Removal of Gold a i d Silver from Sea Water by t. ‘‘ On the Removal of Gold from Suspension and Solution by Fungoid Growths,” N.8.TV., 1895. Muntz Metal Sheathing,” ibid. ; see also Chem. iVews, 1896, 74, 182. Report A d . Assoc. Adv. Science, 1890.COLLIE : PRODUCTION OF PYRIDINE DERIVdTIVES, ETC. 299 Sylvine . . . . , 1.1 grains of gold per ton. Deposit from Salt pan 1.3 ,, Y f 9 9 Kainite , . . . . 1-96 ,, 9 9 9 , Carnallite . . . . 1.2 ,, 7 9 9 9 Chilian nitre . . . 1.69 ,, 7 ) 9 7 As might be expectec?, bittern yielded larger quantities of gold than sen water; one specimen gave 5.08 grains t o the ton whilst another gave as much as 14 grains, but as it was a very old specimen of unknown origin, this result requires confirmation. One specimen of kelp was also found to contain no less t h a n 22 grains of gold to the ton, but as the specimen was also very old and of unknown origin, this result must be confirmed, and I think it desirable to compare the results with those from other kelps.If, however, the sample be a fair one, then I think that the suggestion which I threw out in a previous paper, that it might pay to extract gold as a bye-product in the manufacture of salt, iodine, &c., will, perhaps, be justified. During the next year, I hope to examine further samples of bittern and kelp of both European and Australian origin. It would be extremely interesting to examine the mud and other deposits from salt pans or salterns ; especially from some of the old ones like those of Lymington, which have been used from Roman times, where, if the conditions have been favourable for the retention of the gold, we might find quite noticeable quantities of the precious metal. Another investigation which ought to be undertaken is to determine the amount of gold and silver in various minerals and rocks by more delicate processes than those used in assaying both in auriferous and non-auriferous districts, as it is one which could probably throw much light on the origin of gold in veins and similar deposits. Processes such as are described in the paper on the presence of gold in sea water should be used, inasmuch as the ordinary methods of assay are not sufficiently delicate.