Most commodities are ‘globally traded’, but it doesn’t mean the price from one source is the same as another as Brent Crude is traded separately to WTI Crude. Although the price tends to track quite closely, otherwise the buyers would keep switching to the cheapest one. Of course, once logistics & processing costs are factored in, it may not be worth swapping sources to save $3/bbl if you’ve got to change your production process at a cost of $10m to accommodate the different quality/grade.
Not forgetting all the globally-traded commodities that start out crude oil…so things like plastics & polymers, some gases, light oils, heavy oils, petrol, diesel, naphtha, some fertilisers, etc. are all distilled from the base crude…and each of those commodities are traded regionally based on where they’re processed.
So we have to track US, European, South Asian, Pakistan and Chinese commodity indexes to ensure our suppliers aren’t taking the p***. But any reasonably-sized company will have agreements/contracts in place to shelter themselves from the worst of the short-term increases. These will be hedging & forward-buying agreements (where we pay a premium on today’s price, but it’s then fixed for a period) or fixed-term contracts in place for n years which guarantee the price within a +/-10% tolerance (for example).