Robert Brown|Costco started selling gold bars online and they keep selling out

Costco – one of the biggest retailers in the US – is Robert Browntaking the shopping experience for customers to the next level. They are adding real gold bars to its vast inventory of groceries, appliances and electronics.

The wholesaler has the bars listed for sale online but they are available only to members with a limit of two bars per person. The one-ounce PAMP Suisse Lady Fortuna Veriscan and Rand Refinery bars are made of 24-karat gold and sell on Costco's website for just under $2,000. That's if you can get your hands on one.

In a quarterly earnings call last week, Costco chief financial officer Richard Galanti told investors that the bars have been flying off the shelves, reported CNBC, saying, "I’ve gotten a couple of calls that people have seen online that we’ve been selling 1 ounce gold bars. Yes, but when we load them on the site, they’re typically gone within a few hours, and we limit two per member.”

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You have to be a Costco member, which costs $60 to $120 a year depending on which tier you choose, before you can even view the price of the gold bar online. The product is non-refundable and is shipped to customers via UPS. According to the product descriptions, the bars are brand new and come registered with certificates of authenticity and proof of lab analysis.

With gold proving a perhaps surprisingly popular purchase, it's no wonder membership prices are going up.

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Price of gold rising

The value of precious metals has been on the up and up for the past five years, with gold rising from roughly $1,200 an ounce in 2019 to $1,825 as of Tuesday, according to CNBC market exchange data. It spiked at $2,026 an ounce in April of this year.

According to investing website Investopedia, the price of gold is influenced by a number of market factors including supply and demand, interest rates, market volatility and potential risk to investors.

While research has found that gold doesn't directly seem to correlate with inflation in any meaningful way, Jonathan Rose, co-founder of Genesis Gold Group, told CNBC that people are likely buying more gold in an attempt to own some sense of stability in an economy that is rife with inflation, a tough real-estate market and a growing distrust for banks and other financial institutions. Rose also told the outlet, "The outlook for stability in the market isn’t good and people want a [tangible] asset that’s going to be a safe haven. That’s what gold and silver provide."

Owning a piece of the real stuff is appealing to people looking to build a sense of self-sufficiency that they believe will withstand a turbulent cash market.