Panchaloha (Sanskrit Devanagari: पञ्चलोह; IAST: pañcaloha; Tibetan: ལྕགས་རིགས་སྣ་ལྔ, Wylie: lcags rigs sna lnga) (also called Panchaloham - literally, "five metals") is a term for traditional five-metal alloys of sacred significance used for making Hindu temple idols (Murti). Making Panchaloha images was a well kept secret for a long time and their color changing properties added to their mysticism.
The composition is laid down in the Shilpa shastras, an ancient Sanskrit text on idol making. It is traditionally described as an alloy of gold(Au), silver(Ag), copper(Cu), iron(Fe) and lead(Pb) as the major constituent;
In some traditions, particularly Tibetan, it was considered auspicious to use thokcha, meteorite iron; either as a component of the alloy in general, or for a specific object or purpose. The amount used could vary, depending upon the material's availability and suitability, among other considerations. A small, largely symbolic quantity of "sky-iron" might be added, or it might be included as a significant part of the alloy-recipe.
Practical compositions are Cu, Au, Ag, Pb and Zn; Cu, Ag, Pb, Fe and Sn; and Sn, Cu, Fe, Pb, and brass. Because of the cost, gold and silver are now omitted from the manufacture of general-purpose icons, where copper, brass, and lead in the ratio 29:2:1 are used.
- The Lost-Wax Casting of Icons, Utensils, Bells, and Other Items in South India, R.M. Pillai, S.G.K. Pillai, and A.D. Damodaran, October 2002, JOM.