Costco customers stocked up on gold and silver bars. Now, the retailer's adding a third precious metal

Costco Wholesale ( COST ) is getting further into the precious metals business. While gold bars and silver coins have previously been top of mind for shoppers, the retailer is now adding a third precious metal: platinum.

Costco is selling the one-ounce platinum bars for $1,089.99 on its website, alongside its popular gold bars and silver coins. The platinum bars are available for purchase online only to loyalty members. They cannot be delivered to Louisiana, Nevada, or Puerto Rico.

In April, the company struck gold — almost literally. At the time, Costco was reportedly raking in $200 million each month by selling gold bars, according to a research note from Wells Fargo ( WFC ).

Costco started selling its gold bars last September for $2,000 a pop. By late January, it began to offer one-ounce silver coins in a package of 25 for $675 .

The company recently reported strong quarterly earnings, which were fueled primarily by its e-commerce business , including categories such as: appliances, home furnishings, gift cards, and gold and silver.

Gary Millerchip, Costco’s chief financial officer, told investors during the company’s Sept. 26 earnings call that Costco has been helping customers by maintaining low prices on essential items such as chicken, macadamia nuts, Spanish olive oil, and two-pack baguettes.

“We want to be the first to lower prices and the last to raise prices,” Millerchip said.

The commitment to low prices comes, however, as Costco raises its membership fee for the first time in seven years. As of Sept. 1, individual memberships now cost $65, up from $60, while executive memberships increased to $130 from $120.

Millerchip said the timing of the membership hike was “very deliberate,” noting that the two-year delay was partly due to the impact of COVID-19 and rising inflation. Costco typically raises its membership fee every five years.

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