Thermal Alteration of Silica Minerals: An Archeological Approach

Science  23 Jul 1971:
Vol. 173, Issue 3994, pp. 322-325
DOI: 10.1126/science.173.3994.322


Extensive experiments indicate that the application of heat to flint materials may have conferred an advantage to primitive man in the manufacture of chipped-stone implements. When Florida cherts are slowly heated to between 350° and 400°C and maintained at this temperature for sustained periods, a desirable change occurs in the fracture properties. This alteration takes place when the melting point of the impurities within the intercrystalline spaces is reached; thus the microcrystals of quartz are fitted closer together when materials other than quartz serve as fluxes.