The objects found in the Mississippi valley, formed of copper, which are probably the unaided work of the Amerinds, are chisels, arrow- and spear-heads, knives, and perhaps certain thin plates wrought with designs in the repoussé method. No camp utensils or other objects have been found demanding a knowledge of the properties of the metal sufficient to work it into articles requiring a quantity of copper to be manipulated at once. Cushing maintains[258] that the production of thin plates was an easy matter and he shows how the Zuñis made them, but admitting that the Amerinds of the Mississippi valley could make these plates, it does not prove that they did, for as copper in various forms was very early an article of trade, it is possible that they used the imported article. Cushing explains how the Zuñis, by a process of alternate hammering and annealing and then grinding, produced thin plates, which being pressed with a sharp tool would receive a design. This pressed-out portion could be ground down with a flat slab to sever it from the ragged edges of the sheet, and also to make any desired perforations. The resulting turned-up edges could be hammered flat and they then would be as if cut by a shear. Cushing explains how in the South-west ore was quarried and roasted in an open fire, and then smelted in a sort of oven, the copper or other metal appearing finally at the bottom. Primitive furnaces of this kind he found in the Salt River valley. The singular thing about it is the almost total absence of metal objects in the ruins of the South-west. Aside from several small copper “hawk” bells found in the Salado and other Arizona ruins, I have not heard of any metal object that was not positively European being found in any mound or ruin of the South-west, with one exception.[259] In 1875 a man in my employ in southern Utah told me that several years before that time his uncle either had found in a mound in southern Nevada or northern Arizona, or had obtained from some natives who found it, a small gold image, which he had melted down for the value of the metal it contained. At the time I thought this tale belonged with that of the “lost mine,” but I am now inclined to see a fact in it. It is quite within bounds that one of the small Mexican or Chiriquian figures may have found its way up into this region. [Illustration: SMALL FIGURE OF A FROG IN BASE METAL, PLATED WITH GOLD, CHIRIQUI]