Copper is also found in this vicinity, and not more than two miles from the iron mine. It was first discovered about the beginning of the present century, and has since been worked to great advantage. The most remarkable product of copper is the substance known as malachite. It is found in various parts of the world wherever there are mines of copper, but nowhere else in such quantities as in the Oural mountains. Malachite is nothing more nor less than an oxide of copper. The chemists know exactly how it is formed, but they cannot make it any more than they can make the diamond, though they understand perfectly well the composition of that highly-prized stone. Certain salts in the earth mingle with the copper ore and the water that finds its way through the earth, and these ingredients, soaking slowly downward into crevices and hollows in the rock, form the substance of which the Russians make so much use. [Sidenote: HOW MALACHITE WAS FOUND.] In 1885 the largest mass of malachite ever known was found on the Demidoff estate. The miners, who were working a vein of copper, found some shreds or strips of copper extending downward, and the superintendent of the mine ordered them to follow these shreds, in hopes of striking another vein. The work was pushed forward, or rather downward, and the stray threads of ore were traced in all their windings. Two hundred and eighty feet below the mine, the shreds disappeared, and the superintendent was about to give up the enterprise in disgust and despair, when the men suddenly came upon a huge mass of malachite. It was broken up and taken to the surface, and the aggregate weight of the mass was estimated at seventy tons! It was this lot that supplied the most of the malachite in the Church of St. Isaac, and from it, also, was made the enormous vase which the Emperor of Russia sent to His Holiness the Pope.