Purchases of raw materials which will become a component part of the product being processed are exempt. Purchases of electric power or other fuels used directly in custom processing are taxable at a 1 1/2% special rate of sales or use tax. Purchases of manufacturing machinery or machine parts to be used directly and exclusively in custom processing are taxable at the 1 1/2% special rate. All other purchases are subject to regular retail sales or use taxes.
35 Miss. Code. R. 4-07-02-101