LOS ANGELES -- Costco is expanding the collection of precious metals it sells, with the addition of platinum.

The big-box chain is now selling Swiss-made 1 oz. platinum bars for $1,089.99 on its website, but a Costco membership is required for purchase. The bar features Lady Fortuna, the Roman goddess of prosperity, according to the manufacturer's website.

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Costco is trying to replicate its recent success with gold bars, with platinum joining the extensive list of precious metals that collectors are snapping up at the retailer.

In 2023, it began selling gold bars and sold more than $100 million worth of the bars during the first quarter of that year, the company said in its earnings report. Then, earlier this year, Costco started selling silver coins for the first time, at a price of $675. The coins are non-refundable, and members can purchase a maximum of five.

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However, the price of gold is a better bet for collectors because the price has recently hit record highs. Meanwhile, the price of platinum has risen modestly compared to gold, year to date.

But Costco's move is more about marketing than increasing sales. After all, not many people are actually stashing away gold bars in their homes. It's selling precious metals to try to reinforce its "treasure hunt" brand image where it peppers its stores with unexpected, limited-time items to keep shoppers coming back.

"We try to create an attitude that, if you see it, you ought to buy it because chances are it ain't going to be there next time," Costco's founder once said. "That's the treasure-hunt aspect. We constantly buy that stuff and intentionally run out of it from time to time."

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