After a long time gold, the first known of the metals, appears among the bone ornaments with jet and amber. Irish Neolithic remains are particularly rich in gold. Then, perhaps 6000 or 7000 years ago in Europe, Neolithic people began to use copper in certain centres, making out of it implements of much the same pattern as their stone ones. They cast the copper in moulds made to the shape of the stone implements. Possibly they first found native copper and hammered it into shape.[48] Later--we will not venture upon figures--men had found out how to get copper from its ore. Perhaps, as Lord Avebury suggested, they discovered the secret of smelting by the chance putting of lumps of copper ore among the ordinary stones with which they built the fire pits they used for cooking. In China, Hungary, Cornwall, and elsewhere copper ore and tinstone occur in the same veins; it is a very common association, and so, rather through dirtiness than skill, the ancient smelters, it may be, hit upon the harder and better bronze, which is an alloy of copper and tin.[49] Bronze is not only harder than copper, but the mixture of tin and copper is more fusible and easier to reduce. The so-called “pure-copper” implements usually contain a small proportion of tin, and there are no tin implements known, nor very much evidence to show that early men knew of tin as a separate metal.[50][51] The plant of a prehistoric copper smelter has been found in Spain, and the material of bronze foundries in various localities. The method of smelting revealed by these finds carries out Lord Avebury’s suggestion. In India, where zinc and copper ore occur together, brass (which is an alloy of the two metals) was similarly hit upon. So slight was the change in fashions and methods produced by the appearance of bronze, that for a long time such bronze axes and so forth as were made were cast in moulds to the shape of the stone implements they were superseding. [Illustration: Neolithic Implements] Finally, perhaps as early as 3000 years ago in Europe, and even earlier in Asia Minor, men began to smelt iron. Once smelting was known to men, there is no great marvel in the finding of iron. They smelted iron by blowing up a charcoal fire, and wrought it by heating and hammering. They produced it at first in comparatively small pieces;[52] its appearance worked a gradual revolution in weapons and implements; but it did not suffice to change the general character of men’s surroundings. Much the same daily life that was being led by the more settled Neolithic men 10,000 years ago was being led by peasants in out-of-the-way places all over Europe at the beginning of the eighteenth century.[53] People talk of the Stone Age, the Bronze Age, and the Iron Age in Europe, but it is misleading to put these ages as if they were of equal importance in history. Much truer is it to say that there was: