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Mr. BROMLY‘s letter, dated October 6, 1929, a Preliminary Report

Abstract: Marketing efforts of Mr. H.L. Bermann determined an English Mining Company to send Mr. Bromly as consultant to Böckstein to evaluate the prospects for restarting work at the socalled Siglitz-Bockhart-Erzwies gold mining area. Shortly after having seen parts of the property, he wrote a letter to a friend about his discouraging impressions.

"................... The position at the mine seems very clear. The property covers a large area, and of course I did not see everything. That would take months.

Present interest is confined to two areas or sections, the Rathausberg and the Kolm Kar massives. In both these areas there are numerous and extensive old workings, mostly high up and in the vicinity of the contact between the intrusive gneiss and the overlying sedimentaries. These latter have been largely removed by erosion, but, nevertheless, the old workings seem to be entirely confined to the marginal, or contact zone of the gneiss. The whole district is dissected by deep valleys with steep and precipitous sides, but, despite this, the ancients apparently never worked anything low down. They stuck to the top, high up, in the contact area, which is what one would expect. As far as I could see and learn they never had anything large, only small narrow ore-shoots, but, doubtless, richer than in depth.

It must be considered also that they could work such deposits much cheaper than is possible today and were satisfied with a return which would be useless to modern workers.

The present company first confined its attention to the Rathausberg, where the ore-bodies are rather larger than elsewhere, until the veins were cut off, or died out at a fault, work was abandoned in that section and a scheme elaborated to work the Kolm Kar, or Geisler section, which dad been idle for 200 years. An ambitious scheme of low-level tunneling was commenced and some 6 to 7 kilometers of driving was done. In the course of this, one of the old ore-shoots in the Geisler was undercut, in the contact zone, and about 30.000 tons of ore taken from below the old workings, and milled in a small experimental plant of 20 tons daily capacity. Much driving was done upon a series of veins, or faults, which were cut at depth, and a small amount of ore, approximately 7000 tons was blocked out, and partly stoped and milled , leaving about 5-6000 tons standing there yet.

The drivage at depth has shown that the ore-bodies are very small, narrow scattered lenses, extremely erratic both in occurrence and in extent.

Still over the whole extent of the new workings upon the various veins, there is probably a fair tonnage awaiting development, but practically nothing blocked out. The work has been almost entirely confined to one horizon only, without raising and intermediate drifting. Consequently there are practically no reserves in the shape of ore developed by exposure on three or more sides. With one exposure only, ore found thereby can only be classified as "probable".

It is impossible to measure, or estimate, the total tonnage overhead, from a simple exposure in the roof of one level.

The ores consist mainly of narrow and small bunches of mixed sulphides of a fair grade in themselves alone, but cannot be mined without the admixture of much low-grade vein matter, which results in a milling-grade of about ten grams gold per ton; of which about 65%, roughly, has been recovered in the mill. Taking also into account the silber, arsenic and sulphur, the recovery-value in all has been about £ 1 per ton, at today´s prices.

The costs, of course, have been very much higher, and much money lost, but, if the ore-bodies were only larger and more consistent, the cost could be much reduced on a larger turn-over. The past costs are no guide to what might be expected on a larger scale; but, on the other hand, the larger scale of stoping would result in more dilution, and proportionally lower values.

Doubtless, additional development will increase the reserves, and if exploration be continued long enough, there is always a chance of finding something bigger and better. We have to remember however, that the old-timers do not seem to have found anything large, and certainly the modern work has not done so.

On the whole, the probability of making a profit, under modern conditions, seems remote, and the property is, as far as I can see a difficult one to handle and almost certainly a money-loser. Work in winter is difficult.

If we can find a way to get Mr. Bermann out without loss we must try our best to do so, but it is difficult. We went into matters very fully and the management gave us every help and assistance, but, with the exception, perhaps, of Dr. Imhof, the difficulties of the problem are fully realised.

It is hopeless, of course, to expect to float a large company at the moment, and the question is, can anyone be found willing to risk money in further development ?

That, in a nutshell, is the problem.

Please excuse the length of this, but I want you to know the facts without having to wait for the report itself.............."







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