Terms for the Purchase of Bulk Concentrates

The terms for mixed bulk concentrates represent a mix between standard zinc and lead concentrate terms and the following is a typical example  

Penalties and refining charges are similar to lead concentrate terms and often there can be additional penalties, such as for silica above a minimum level. This critically depends on the mix of feed stocks normally received by the smelter. 

The treatment charge is commonly US 10 to US 15 above the ruling treatment charge for standard zinc concentrates, at around US 220 per tonne, and with the price escalator three per cent lower than standard zinc concentrates at around nine per cent. 

---