"The SB text is famous for containing references to the wide spread of metallurgy during that period, none perhaps as important as the following (SB.13.2.2.15-18): for the horse is the nobility (chieftain), and the other animals are the peasantry (clan); and those who do this really make the peasantry equal and refractory to the nobility; and they also deprive the Sacrificer of his vital power. Therefore the horse alone belongs to Pragapati 1, and the others are sacred to the gods: he thus, indeed, makes the peasantry obedient and subservient to the nobility; and he also supplies the Sacrificer with vital power. The slaughtering-knife of the horse is made of gold, those of the ëparyangyasí of copper, and those of the others of iron; for gold is (shining) light, and the Asvamedha is the royal office: he thus bestows light upon the royal office. And by means of the golden light (or, by the light of the gold), the Sacrificer also goes to the heavenly world; and he, moreover, makes it a gleam of light shining after him, for him to reach the heavenly world. But, indeed, the horse is also the nobility; and this alsoóto wit, goldóis a form (symbol) ofthe nobility: he thus combines the nobility with the nobility. And as to why there are copper (knives) for the ëparyaEgyas,íóeven as the non-royal kingmakers, the heralds and headmen, are to the king, so those ëparyangyasí are to the horse; and so, indeed, is thisóto wit, copperóto gold: with their own form he thus endows them.And as to why there are iron ones for the others, óthe other animals, indeed, are the peasantry, and thisó to wit, ironóis a form of the peasantry: he thus combines the peasantry with the peasantry."