Glossary
LME — London Metal Exchange — definition
The international exchange that sets the reference price for aluminium and zinc, and therefore a substantial part of the price of a casting.
We price castings on metal weight consumed plus cycle time. When the metal price moves, the part price moves with it.
That is an argument for transparency about the pricing model rather than a fixed price that hides the exposure. You should know how much of the part price is metal, because that is the part that fluctuates.
Practical consequence: quotations have a limited validity, and long contracts should carry a price adjustment mechanism tied to the metal quotation. That protects both parties — including you, when the price falls.