Study of Ancient Cements

There are various reasons to study the composition of ancients cements. The actual composition of a cement, for example, provides information on its nature, the technology used for making it, and the provenance of its components (Middendorf et al. 2005). It may also elicit differences between the nature of an original cement used for building and that used for later repairs (Streicher 1991 Jedrzejewska 1990). Most analytical work concerning ancient cement in the recent past has been based mainly on the use of optical microscopy and classical analysis techniques. Sometimes, such studies are complemented with information derived by instrumental techniques (Blauer-Bohm and Jagers 1997). 

Archaeological Chemistry, Second Edition By Zvi Goffer Copyright 2007 John Wiley Sons, Inc. 

Metal Chemical symbol Abundance in earth s crust (ppm) Density (g/cm ) Melting point (°C) Hardness (Mohs scale) 

FIGURE 34 Melting point of the metals and alloys of antiquity. Heating techniques to attain temperatures higher than about 1500°C were deveioped as recentiy as the late nineteenth century. Only metals and alloys melting below 1500°C were, therefore, smelted in antiquity. 

The 92 chemical e/emenls that occur naturally In the earth can be divided into two main groups metals and nonmetals. Although the distinction between the two is not always sharp and clear. It can be said that over 70 of the 92 elements are metals among the fewer than 22 remaining non-metals, six are known as metalloids, which have properties that fall between those of metals and nonmetals (see Appendix I). 

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