Ax questions, hard answers.Another hypothesis for the polish on the Stone Age corundum corundum (kərŭn`dəm), mineral, aluminum oxide, Al2O3. The clear varieties are used as gems and the opaque as abrasive materials. Corundum occurs in crystals of the hexagonal system and in masses. ax head is that the Stone Age people never had absolutely pure corundum, which indeed would have required diamond to polish ("In the Buff: Stone Age tools may have derived luster from diamond" SN: 2/19/05, p. 116). It is possible that these people used one grade of corundum to make the ax head and a slightly harder grade to polish it. The difference in hardness would serve the purpose. JAMES E. BURKART, BETHESDA Bethesda, city, United States Bethesda, uninc. city (1990 pop. 62,936), Montgomery co., W central Md., an affluent residential and commercial suburb of Washington, D.C. The area was settled in the late 17th cent. , MD. Researcher Peter J. Lu says that his group tried pure corundum, the highest-grade possible, as well as quartz quartz, one of the commonest of all rock-forming minerals and one of the most important constituents of the earth's crust. Chemically, it is silicon dioxide, SiO2. and diamond, to polish the ax. Only the diamond produced the smoothness of the original cave heads.--A. GOHO The article was very interesting. In looking at the photo, however, the first question that came to my mind was, How did these Stone Age craftsmen create the large round hole through the ax? JOE SARDINA Noun 1. Sardina - pilchards genus Sardina, genus Sardinia fish genus - any of various genus of fish Clupeidae, family Clupeidae - herrings; shad; sardines; etc. , FAIRPORT, N.Y. |
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