Basic Information
The Stone Age is a historical/anthropological term that describe either the prehistorical era prior to humanity gaining general use of metal working technology or, more broadly, technologies which predate the use of metal. The overall stone age is thought to have ended by about 2000 BC, but is arguably still going on amongst a few isolated human tribes (and, as far as well can tell, all non-human tool users1) exact end dates are hard to pin down and vary from place to place - trade in artifacts can also muddy archaeological evidence and there is a growing field of archaeology which looks for minute clues in the impurities of metal items to attempt to track down where they were mined and/or forged to determine this sort of thing.
As will be obvious, "the stone age" covers a lot of human history and a vast range of developments, collated only by the lack of metal tools. The age is traditionally subdivided into the Palaeolithic ("old stone age"), Mesolithic ("middle stone age") and Neolithic ("new stone age") eras based on the complexity of tools and other structures, processes and items associated with a given culture or find. The chalcolithic ("copper stone age") is also sometimes tacked on the end to mark the transitional phase at which limited use of soft metals was in progress.
In the normal reckoning, the stone age terminates in the Bronze Age, with bronze appearing as the first hard metal to serve as a generic from which tools could be made - this is not always the case everywhere as, for example, sub-Saharan Africa doesn't really demonstrate a bronze age (possibly due to a scarcity of workable tin resources, and appears to move from chalcolithic to iron … if the transition was ever made without external intervention. As already hinted at, it was possible to have a fairly advanced society with mainly stone age technology - most of Central America produced thriving civilisations without mastering bronze, and some of the sub-Saharan African civilisations may have done likewise. Eurasia's earliest cities seem to have formed even before the chalcolithic (even if those seem to have then died out again, possibly due to poor agricultural technology leading to a food crisis).
As above, trade and exchange can also play a part in technological development - technology may spread along trade routes, but it is also common for external trade to suppress a domestic industry: a culture which can afford to buy the tools it needs from another may struggle to develop its own metallurgy. Alternatively, only part of a technology tree may be unlocked - a culture may learn to smith in a metal, but never to mine and refine it (for example if it lacks the relevant deposits for mining).
Sources
Game and Story Use
- Actually playing in the Stone Age can give a game a totally different feel - even a Hollywood Stone Age with more advanced social and economic structures but a lack of metal (like a more serious version of The Flintstones) … a more realistic campaign will need to account for the lack of anything remotely resembling civilisation in most cases.
- Note that stone age equipment is almost universally inferior to metal using equivalents - stone weapons should be less resilient and less effective than, say, steel, armour should be subject to similar strictures armour and various other things will be more complex to work around.
- It's worth noting that even something as simple as the ability to make a bronze axe head greatly increased humanity's ability to cut wood and clear forest, which in turn could lead to larger structures and more agricultural land. Likewise even copper chisels improved stoneworking capacity considerably. Plenty of other examples exist.
- Note that in sci-fi and fantasy workarounds to metal may be found by appropriately skilled cultures by using biotechnology/biothaumaturgy/other magic to change the properties of naturally occurring materials. Also, magic (or sufficiently advanced technology) may bypass some aspects of the metal working process (maybe even as far as converting ore directly into fashioned items2).
- Also note the matter of trade - and of the interspecies aspect of things that starts with the chimpanzee and the paper clip - metallurgy might be learned from the dwarves rather than invented by humanity, or humanity might never master iron smelting, working entirely with pigs of iron sent down from dwarvern mines. How much of a claim to being a metal worker you have may be in doubt if what you use is made by another species.