chert noun Pronunciation: 'chert', 'chat'
Chert is a sedimentary rock. Chert is a more inclusive term than flint or jasper, two other cryptocrystalline silica rocks. Flint is a dark, hard chert like the rock that prehistoric stone tools are made from, and jasper is a bright, reddish chert associated with iron-rich deposits.
“Lith” means stone e.g. Megalith, Monolith, Microlith. A lithic is simply a stone tool instead of a stone monument. The main definition is a tool that has been made from raw stone material; this covers all periods from all places over the globe. The term “Lith” is also used within the stone tool categories, such as “microlith” which was a type of tool in the British Mesolithic (a category of tools that were very small flake struck off a core then retouch to make sharp cutting tools and points). There are many different types of stone that can be used to make lithic tools, depending on where you are in the world.
Britain has plenty of flint and Bio-sedimentary materials, whereas North America has igneous material. Different materials required different techniques to work them into effective tools. Some materials produce a sharp cutting edge naturally when flaked e.g. Obsidian and flint. Other materials have to be physically changed to make them useful e.g. some jaspers have to be heat treated to make them workable.
So what is flint? By mineralogical definition, flint is simply black chert. It appears that the term "flint" was originally applied to the high quality black cherts found in England. Over the years names have evolved for local chert formations/deposits that may include the word "flint" and technically speaking these would be incorrect more often than not. The reality of the flint verses chert debate is that in most cases it is something like "splitting hairs", there really is very little difference, chemically speaking. Artifact collectors tend to call materials that have a more waxy luster "flints" and those which have less luster to no luster "cherts". The difference between them lies in their purity relative to pure quartz and their matrix particle size. The smaller the particle size and the purer the material, the more likely we collectors would be to call the material flint. To a purist, we would be wrong. A generalist would say "close enough".
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