Good point. This was especially important back in the Hunt brother's silver debacle of the late '70's. People often say silver got to $49 an ounce. NO! "Good delivery bars" got to $49; I never saw silver or silver coin over $35. A good delivery bar is an approximately 1000 oz bar produced by a refiner approved by the commodity exchange. If you shorted a 1000 oz contract, you either had to buy back the contract, or deliver a good delivery bar to an approved warehouse. [Well, actually, most likely nothing ever physically moved; one commodity broker just transferred ownership of a bar already in storage to another broker.] And no, you could not come in with 1000 oz of silver US coins and satisfy your delivery obligation; only good delivery bars could do that. The approved refiners stopped refining for the public; they would only refine for their own account. Why refine for anyone else if you could buy junk silver at $35, spend a few cents per ounce refining it, then sell for $49? So there was a "squeeze" on good delivery bars, just like stock speculators can engineer a squeeze on a company's stock.
pssst ... All I know is space travel, wouldn't have been possible, if it wasn't for the avocado. A - It Rhymes; B - is vaguely correlated to veganism with the avocado; C - teaches us a fact that is false, though is still a stated falsely fact; D - it's confusing jibberish to enlighten the day; or E - All of the Above