Denver.—The Ajax Gold Mining company, operating on Battle mountain, is considering the erection of a milling plant.

Cripple Creek, March 18. (Special Correspondence)—At the meeting of the stockholders of the Ajax mine, held at Denver last month, the proposition of the company building its own mill was brought up. It was favorably considered, and the construction of the plant should take place in the near future.

THE CLANCY PROCESS IN CRIPPLE CREEK.
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The first step toward the establishment of mills in Cripple Creek, based upon the variations of the cyanide process patented by John Collins Clancy, will be taken at the property of the Ajax Gold Mining Co., of which Judge E. A. Colburn of Denver is the principal stockholder.
Excavations for the plant have already been made, and it is expected that it will be ready for operation by May 1. The initial unit will have a capacity of 100 tons, while the buildings will be designed to increase the capacity to as much as 300 tons after the first unit has given satisfaction.
The cyanide plants in operation at the Portland and Stratton's Independence, at the former of which a variation of the cyanide solution is used, though never officially described, are operated in conjunction with concentration. The Clancy method in itself does not contemplate the recovery of the gold by any other means than that of chemical solutions; indeed it is a chemical process strictly, the principal features of which are the use of cyanamide as a means of regenerating cyanide solutions and the electric current.
The inventor's descriptions were published in Mining Science under the dates October 20, 1910, and January 5, 1911.

The Ajax plant will have tube mills for the fine grinding of the pulp, the grinding being effected in the solution. The system of agitation is not stated as yet, but the Moore filter will be used, according to Mr. Clancy's recommendation. The mill is to be situated between Squaw and Battle mountains, just above the town of Victor.

Machinery for the new 100-ton capacity mill, to be constructed by the Ajax Gold Mining Co. on its Battle mountain property has been hauled to the mill site. Graders are at work, and the construction work will shortly be commenced.

The First Cyanamide Process Installation.
It is rather complimentary to the soundness of the principles of the Clancy cyanide process that within a few months after they were publicly announced a Colorado company decided to erect a mill embodying them.
The Ajax Gold Mining Company, with mines at Victor, Cripple Creek mining district, Colorado, is erecting a 100-ton unit for the treatment of raw sulpho-tellurides by the Clancy process.
The ore will be crushed dry, ground in tube mill with cyanide solution, agitated in tanks with the addition of potassium iodide and the application of the electric current; then, with the addition of calcium cyanamide, the solution will be regenerated in the same agitation tanks.
The pulp will be filtered by the Moore system and the solution returned for further use.

Preliminary experiments in a laboratory way have thrown more light on the details of commercial operation. For one thing, it has been found that no such current densities as first proposed will be necessary for either extraction or regeneration.
The extraction occurs with currents as low as 2 amp to 3 amp, and some experiments have indicated that still lower currents will produce the result desired. The regeneration of the solution also has been accomplished with similar currents and the same solution used for eight to ten weeks has shown little loss of strength.
The proper substance to be used as anode is one that has not been settled, although the choice probably rests between fused ferric oxide and Acheson graphite.

Construction of the plant is now under way and the first operation should take place early in the coming summer. The result will be watched for eagerly, as its success will mean much to the Western field. Present laboratory indications are very favorable for success in the commercial application.

The Colburn mill at the Ajax property, which will use the Clancy process, will be a 200-ton unit instead of 100 tons as at first planned, according to announcement made a few days ago.

A set of sampling rolls has been delivered to the Colburn mill on the Ajax property, now in the course of construction. From now on the machinery will be arriving every day. It is announced by Superintendent Colburn that the mill will be in operation by June 1.

The building for the main mill of the Colburn plant, now in the course of construction on the Ajax property, is going up and the sampling plant has been constructed. All foundations for the new plant have been laid.

The framework of the new mill is being put up and the machinery installed. The sampling building has been housed and it is predicted that the Colburn will be ready for starting within two months.

The Colburn mill is being constructed as fast as possible and the roof has been put on the main mill building. All of the machinery for the sampler has been set in place.

While an official statement will not be made as to the time the Colburn mill will be started, it is predicted that the mill will be in operation by Oct. 15. The large steel tanks, which have been on the ground three weeks, are being set up and put in place.

A. W. Warwick, mining and metallurgical engineer, western representative of the Moore Filter Co., is in Cripple Creek to supervise the starting of the Colburn mill, in which the Clancy process is to be used.

Ajax—The Clancy process will soon be in full operation, it is said. Crushing has commenced and the 500-ton tanks will be filled at once. A. M. Warwick is manager.

Superintendent E. A. Colburn, Jr., of the Ajax, has given out word that the construction for the Colburn mill is about completed, all of the machinery being installed, and all that remains is the adjusting of several parts of the mill.

October marks the completion of the Colburn mill, a 200-ton plant constructed on Ajax ground, Battle mountain, for the purpose of treating the entire product from this mine. The Clancy electro-cyanide process is used.

The Clancy Process.—In our issue of January last we gave a long abstract of a paper by J. C. Clancy describing his cyanide process, in which calcium cyanamide is used as the source of cyanide. In Mining Science for November 9, A. W. Warwick, chief metallurgist to the Moore Filter Co., which owns the process, describes the new plant erected at the Ajax mine, Cripple Creek, for the purpose of treating low-grade sulpho-telluride ores that have not so far been profitable.
Mr. Warwick prefaces his article by saying that the plural is necessary for describing the ores of this mine, as there is a great variety of them, and it has proved advantageous to keep them apart when treating them by the Clancy process.
Readers of our former article will know that in this process the solution contains calcium cyanamide, potassium cyanide, sulpho-cyanide, and iodide, and that the solution is electrolysed with the object of obtaining the nascent oxygen required for the reaction. The sulpho-cyanide and iodide are not lost, and the solution can be used over again, the necessary cyanide being obtained by the continual addition of cyanamide.
During the experiments at the Ajax plant, the important discovery was made that much less electric current can be used than was at first supposed, and thus a cost that might have threatened the process has been removed. Here a current density of only 5 to 7 amperes per square foot of electrode is used, instead of 50 as originally figured.
This makes a great difference, and during a 24 hours agitation the energy required will only be from one-tenth to one-seventh of a kilowatt per ton of ore, instead of 4,5 kilowatts.
The plant has a capacity of 200 tons per day. The ore is crushed in rolls and then reduced to 150 mesh in tube-mills, the solution being introduced in the latter. Subsequently the pulp is sent to agitators having a capacity of 80 to 100 tons dry, the ratio of ore to solution being 1: 1½.
In each agitator is 20 electrode-baskets, each having an anode surface of 4 sq. ft. and a capacity of 35 amperes. After agitation the pulp goes to Moore filters and the solution zinc-dust precipitation-boxes. The movement of the pulp is effected throughout by air-lift. The results obtained at this plant will be awaited with unusual interest.

THE COLBURN MILL.
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Mining Science is reliably informed that the Colburn mill at Cripple Creek, which is erected on the property of the Ajax Gold Mining Co., has been meeting with satisfactory results during the few weeks in which it has been in operation.
This plant was described in Mining Science of Nov. 9 last. It is handling the Ajax dump at costs that compare favorably with the work of the other mills of the district. No official statement is to be had at this time. It will be remembered that this is the first plant to install the Clancy Cyanide process, owned by the Moore Filter Co. of New York.

Denver Dec. 9—The Clancy plant, at the Ajax, is in operation and will have its tonnage to report for December.

Much of the low-grade ore is now being treated by mills at the mines. A recent acquisition to the list is the Ajax. This mill has just been completed and its most notable feature is the use of the Clancy process for treating raw telluride ore.
This involves the use of calcium cyanamide and the electric current. The process is little understood as yet, and as this is the first instance of its application upon a commercial scale, the results of an extended trial will be awaited with much interest.

It is stated that the Colburn mill is running about half capacity now or 100 tons a day and that a higher percentage of extraction is being made.

A clean-up is now being made of the precipitates in the Colburn mill. The retort should net about $20,000, which will result from the treatment of 6,000 tons of ore worth almost $4 a ton.

THE COLBURN MILL.
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That the Colburn mill on the Ajax property at Cripple Creek is a complete success is the declaration of Judge E. A. Colburn, president of the company, in an interview at the camp.
The cleanup after three months of operation resulted in a retort of about $14,000. The value of ore treated was $16,000. This indicates that the Clancy process is dissolving the gold.

The Colburn mill is handling 100 tons a day, according to Judge Colburn, and the ore is running $1.60 to $3 per ton. One batch of $19 ore was put through the mill, but the tailings did not increase in value.
The tailings assay 80 cents per ton.

5-ton experimental plant will be erected at once near the ore house for the purpose of perfecting the chemistry of the process. In this plant ores from every camp in the world will be tested.

The Colburn mill will be enlarged to handle 350 tons daily. In referring to the Portland mill. Judge Colburn said it was highly satisfactory and successful, but he believed that by his method a higher extraction will be possible at a lower cost.

With the clean-up now in progress completed, the Colburn mill on the Ajax Gold Mining Co.'s Battle mountain estate will be temporarily closed down.

The Colburn mill, using the Clancy-Moore electro-chemical process, which was closed down about six weeks ago to make repairs, will not be started up before Sept. 1, according to the superintendent of the property.
The sampler is being rebuilt.

The Colburn mill will resume operations about the first of September.

The tram from the Ajax dump to Squaw mountain, which will be used to carry the waste rock from the ore house to make a fill across the gulch in order to dam the tailings from the Colburn mill, was started in operation last week.

It is announced that the Colburn mill at the Ajax mine, which uses the Clancy process and which has been closed down for nearly three months while the sampler was being built, will be ready for operation and the reception of ore Oct. 10.

Since the Colburn mill on Battle mountain has been started up after a long shut down the average daily tonnage put through the mill was 78 tons. The ore is coming entirely from the dump. It averaged $3.25 last month.

According to local statistics, the following Cripple Creek mill gold production was:

Name
Tons.
Av. val.
Gross value.
Colburn Ajax
4,245
2.59
11,674

According to local statistics, the following Cripple Creek mill July output was:

Plant
Tons
Av. val.
Gross value.
Colburn-Ajax
4,400
2.84
12,496

During July, eight of the local mills, the Portland, Stratton's Independence, Colburn-Ajax, Kavanagh-Jo Dandy, Gaylord-Dante, Rex Mining & Milling Co., Wild Horse, and Isabella plants, treated 35,373 tons of ore with a gross value of $85,428.
This low-grade ore ranged in value from $1.10 to $2.84 per ton, with a general average value of $2.41 per ton.

According to local statistics, the following Cripple Creek mill August output was:

Plants
Ore treated tons
Av. val. per ton
Gross val.
Colburn-Ajax
5,580
$ 3.20
$ 17,856

The reported production of the following district mill during September was as follows:

Plants
Tonnage
Av. val.
Gross val.
Colburn-Ajax
5,285
3.25
$ 18,931

A new tube-mill and more powerful electric motor are to be added to the plant at the Colburn mill owned and operated by the Ajax Gold Mining Co.
The November production will be about 7100 tons of ore. The mine is shipping ore to both custom and its own mill for treatment.

The Estimated production of the following district mill during November is as follows:

Where treated
Tons
Av. value
Gross value
Colburn-Ajax
5,000
$ 4.00
$ 20,000

During 1913 the electro-cyanamide process, originally installed at the Ajax mill, Cripple Creek, was finally abandoned in favor of combined concentration and bromo-cyaniding.