In a brief review I may recall the more salient points regarding the use of metals in ancient Chiriqui. Gold, silver, copper, and apparently tin are represented.
Gold and copper were very plentifully distributed among the isthmian races, but we have little information as to the sources of supply. Free gold is found in the stream beds of many localities, and copper was probably found in its native state in some convenient locality; yet it is not impossible that these metals were transported from distant regions, as the inhabitants of Chiriqui must have had considerable intercourse with those of Central America on the north and with those of Granada on the south. Silver and tin are found in alloys with gold and copper, but not as independent metals. The silver gold alloy is probably a natural compound. In no case have I found silver to exceed 6 per cent. of the composite metal. Tin was artificially alloyed with copper, forming bronze. The latter metal resembles our ordinary bronze in color and hardness, but I am unable to secure more than a qualitative analysis on account of the scarcity of specimens available for the purpose. We have no information in regard to the origin of the tin. It is not found in a native state, and since it seems hardly probable that the Chiriquians understood smelting ores we are left in doubt as to whether it was obtained from more cultured nations to the north or to the south or from transoceanic countries.
The gold-copper alloys appear to range between pure gold and pure copper. If the bronze is of European origin, then we must conclude that all objects made of that metal are of post-Columbian manufacture. This question will probably be definitely settled in the near future.
The greater number of the objects were formed by casting in molds. Hammering was but little practiced, excepting, apparently, in the formation of sheet gold, which was probably an indigenous product. Repoussé work is not found, save as represented in the crimping and indenting of gold leaf. Engraving and carving were not practiced. It may be considered certain that gilding, or at least plating, was understood.
The objects are obtained from ancient graves of which no record or reliable tradition is preserved. They are all ornaments, no coin, weapon, tool, or utensil having come to my notice. The absence of utensils and of hammered objects of any kind strikes me as being rather extraordinary, since it is popularly supposed that, in the normal succession of events, hammering should precede casting and that utensils should be made before elaborate ornaments.