<P> One of the most important sources of history in the Indian subcontinent are the royal records of grants engraved on copper - plates (tamra - shasan or tamra - patra; tamra means copper in Sanskrit and several other Indian languages). Because copper does not rust or decay, they can survive virtually indefinitely . </P> <P> Collections of archaeological texts from the copper - plates and rock - inscriptions have been compiled and published by the Archaeological Survey of India during the past century . </P> <P> Approximate dimensions of copper plate is 9 ⁄ inch long × 3 ⁄ inch high × 1 / 10 (to 1 / 16) inch thick . </P> <P> The earliest known copper - plate, known as the Sohgaura copper - plate, is a Maurya record that mentions famine relief efforts . It is one of the very few pre-Ashoka Brahmi inscriptions in India . </P>

Why did kings have inscription carved on copper plates and temple walls