The Miami Copper Company-

Miami Copper Company. Story of a Great Copper Mine

The Miami Copper Company at Miami, Arizona

The Miami Copper Company at Miami, Arizona, is one of the notable successes in modern large-scale, low-grade copper mining. Smart mining enterprise, some of the best mining minds in America, and high-type mining personnel have resulted in the success of a property that at one time was considered depleted of recoverable mining wealth. From 1911 through 1939 the Miami Copper company has produced 1,362,575,049 pounds of refined copper with net earnings of over $40,000,000.

Here is a saying among the miners at the Miami Copper Company's mine at Miami, when they speak of muck, that "if it won't grow potatoes, it's ore." That is merely jesting reference to the fact that the orebody of the Miami Copper is a low-grade orebody; yet in the annals of copper mining, the Miami Copper stands out as a conspicuous success, and today it is one of the great mines of our state and nation. There are all sorts of mines gold, silver, lead and copper. There are mines that have values in almost everything that comes out of the ground. There are rich, high grade mines. There are copper mines, not only of high copper content, but there are copper mines rich in copper, whose ore is also "sweetened" by the valuable presence of gold and silver. When you run a copper mine on 0.85% copper ore with only a whisper of gold or silver and you get only about 14 pounds of copper from each ton of ore mined when you do that and are able to keep your shop open on the prices for which copper has been selling these recent years your mine is being run by "smart mining" methods.

In the distance is silhouetted the International Smelter, which handles most of the Miami copper output. The tank in the mid-foreground receives tailings from the mill. Here surplus water is salvaged for reuse.

It takes good miners to make a big mine pay, and the Miami Copper company has some of the best. Unusually fine employer-employe relations results in team work. Conditions are such there is very small turnover. This is part of the "four o'clock" shift lounging about ready to go underground. Wages are based on a sliding scale with the price of copper, an agreeable arrangement. There have been no labor troubles at the Miami Copper company for many years.

option to acquire the claims for $150,000 in cash and one-twentieth interest in any company that might be formed to equip and operate the property. The option was free, with first payment of $50,000 due in six months.

Two shafts were started by the General Development company in 1906. Early results were discouraging and with the financial panic of 1907 a wire came to suspend operations. Newman, when he saw the telegram, tore it up and said he would guarantee wages. The shaft was sunk from 200 to 220 feet when miners entered disseminated ore assaying three per cent copper. An other great orebody had been found. New man received his first payment of $50,000 in June, 1907. When he died in Santa Monica in 1928, he left an estate valued at $12,000,000. The Miami Copper Company was organized in Delaware in March, 1908. Shares were offered for sale direct to the public through a prospectus of March 28, 1908. Concentrating its first ore in 1911, it had This is a view of the head frame over No. 5. Ten-ton skips working with precision belch some 15,000 tons of ore into the crusher bins each day. For the year 1938 production averaged 22.4 tons per man shift in the mine department (including mine machine shop, framing shed and mine time office.) When the bell rings, another cage load of miners will go down underground. The Miami Copper company believes in the policy of getting good miners who know their business, treating them well.

by 1925 paid dividends totaling $30,000,000 or $40 per share on stock that had cost the public $5 in March, 1908. In 1909 B. Britton Gottsberger became general manager of the mine, and he held that post until 1919 when he was succeeded by the assistant general manager, Francis W. Maclennan. Maclennan was succeeded upon his retirement to the position of consulting engineer by A. S. Winther, an executive with wide mining experience, and Robert W. Hughes, one of the best mining engineers in the business, became mine superintendent. The Miami Copper company has always had the best mining brains obtainable to run its mine.

The ore mined at the Miami Copper company contained 2:5 to 3:0 per cent copper at the start but as operations extended it became progressively leaner. Recovery had tended to improve as new methods were developed, but finally the Miami Copper company came to the point of either liquidating or introducing radically new methods of A loaded train, bound for the dumping platform, goes under automatic sprinklers, to settle dust. The haulage level, on the "720 level," is kept spick and span, dust kept down to a minimum.

mining and recovery to make real low-grade ore pay. In 1924, it is reported, liquidation was seriously considered. Had the mine died then, as A. B. Parsons points out in his enlightening book "The Porphyry Coppers," the Miami Copper company would still have gone down in history as a great producer and a great copper mine.

But in 1924, the Miami Copper company's mine at Miami arose to greater splendor.

Drilling hard rock is a man's job but modern mining uses machines whereever possible. These miners wear respirators when actually drilling. Water It is used in drilling to settle dust. "Happy" Woods, on the right is an old time Miami miner.

A new plan of mining, treatment and concentration had been worked out by Mr. Maclennan and his assistants. It would require the investment of a large sum of money to prove its worth or its failure. That was the decision that had to be made by Adolph and Sam A. Lewisohn, ranking officers of the company. They indicated their faith in their men by approving the proposal which called for the expenditure of $1,500,000 for new equipment in the mine, concentrator, and power plant, and for $1,500,000 for a large amount of preparatory work in haulageways, drifts and raises. Every nickel had to be spent before it could be found whether that $3,000,000 was money thrown down a hole or was a wise investment. You can easily visualize the excitement when the time came for all the wheels to A miner working at one of the "grizzlies." Here ore mined above is pulled to the "grizzly" where railroad rails, 10 inches apart, "screens" ore going down to the bins on the haulage level. Rocks have to be broken to proper size.

An automatic mucking machine in the end of a drift. When the machine is in operation, the miner wears a respirator. A mucking machine in operation performs like a mechanical man.

Roar in action and every man on the hill was called upon to deliver his best to find out whether the Miami Copper could make copper ore carrying less than one per cent of copper pay. A goal had been set. Ore had to be handled and treated for so much a ton to pay. When the test was run, the costs came to even a lesser amount than had been set and the Miami Copper turned a new leaf as a copper producer and long, long years of life was assured.

It was personal triumph in technical en-terprise for Mr. Maclennan and those de-partment heads who worked with him in perfecting new methods of mining. It was a triumph for mining engineering ability and a triumph for a big mining or-ganization.

Haulage level at the mine is a network of railways used for trains hauling ore. Four trains of 30 four-ton cars are in motion over the nar-row gauge railroad. Everything functions with precision and speed, flawless efficiency attained to produce the best results. Such safety care is taken that there has been no fatal accident in years.

The William Lawrence Saunders gold medal, the greatest honor that can be bestowed in mining, was awarded to Francis W. Maclennan in 1931 by the American Institute of Mining and Metallurgical Engineers for “his achievements in mining methods which created ore out of rock.” The whole story of the Miami Copper company can be illustrated by a couple of simple figures. In November, 1930, the ore as mined and treated contained less copper than a ton of tailings rejected 15 years before. In the first three years of operation at the Miami Copper tailings discarded from the concentrator, that is, waste from the mining and milling process, conDumping a car is a miracle in motion. Ore so dumped goes into the bins where the skips lift it to the surface for crushing and milling. A car at the station is dumped in a few seconds. Compressed air is used to dislodge wet muck.

This chute gobbles the ore that comes from the mine conducting it to the storage bins in the crusher. A 1,400-ton circular bin takes the mine-run ore that has passed through underground grizzlies with 10-inch spaces.

The mill and concentrator at the Miami Copper company is a maze of big machinery, operating as if by some supernatural force. Ore from the crusher is sent through the ball mills, ground to fine powder. By flotation copper values are separated from tailings and as concentrates are sent to the smelter. The Miami Copper company handles sulphide and mixed ores, have special processes for both. Oxide copper minerals undergo leaching processes, are recovered as copper cement. A small amount of molybdenum is also recovered by special process. Much of the success of the Miami Copper company has been due to the successful milling and concentrating processes. Tained 14.52 pounds of copper per ton. Now there isn't that much copper in a ton of ore mined at the Miami. That's what happens when smart men and smart mining get together in a plant.

In accepting the William Lawrence Saunders award Mr. Maclennan paid homage to those men who worked with him during those crucial months of reorganizing the mining and milling processes at the mine, and bespoke his indebtedness to other mining men who had made advances and improvements in mining and milling processes that had inspired the work in part at the Miami Copper company. In reply to which that eminent mining commentator, A. В. Parsons in "Porphyry Coppers," has this to say: "All that Maclennan says is as true as it is graceful; yet it was Maclennan and his own staff who devised the particular touches that made the method so successful; who developed the scheme of organization and systemization; and who bridged the broad gap-particularly broad in underground operations between a splendid plan and putting that plan into actual practice. The Miami achievement is a bright chapter in the history of the Porphyries and this holds true, no matter what the future of the property may be."

The Miami Copper company and the Inspiration Consolidated Copper company are two separate companies mining the same ore body near Miami, Arizona. Each company (Turn to Page 36) A big mine is mined on paper in the mine engineering office. Mining engineers direct mining operations, with all processes carefully worked out with engineering precision on paper. Here every detail of the mining operation is plotted and planned, cost and efficiency sheets minutely studied to attain the most efficient results.

A pipe line carries tailings from the concentrator to the tailings dump at Solitude Gulch, a distance of 6 miles. In the early days of the company more values were lost in tailings than is regained now from newly-mined ore.