Costco’s (NASDAQ: COST) CFO Richard Galanti is surely happy about the latest news coming from one of its stores. Costco had to do a double take after seeing a single purchase that was recorded at nearly $400,000 (yes, that’s 5 zeros). What was the purchase? A single diamond ring. The sale of such a high priced item was significant for the chain. Costco has nearly 500 diamond rings for sale on its website, with the highest being priced at $419,000. While most people aren’t spending that kind of money on an engagement ring, the recipient of such a ring will surely be delighted. As a result of this expensive purchase as well as other big-ticket items “like golf simulators that sold for $14,000 each” Galanti explains, Costco saw a nice bump in quarterly earnings.