Australian shoppers at discount retailer Costco might be surprised to find a diamond ring worth nearly $1 million nestled in among the giant packs of toilet paper and bulk batteries.

On Sunday, Sky News reporter Jennifer Bechwati found a 6.55-carat ring, priced at $499,999.99, lurking in the aisles of the company’s Canberra store and shared a photo of the unusual item to Twitter, garnering hundreds of stunned comments.

It turns out the rock is one of several “wow” items stocked in each of the company’s nine Australian stores, including a $875,000, 13.72-carat yellow diamond at Costco’s Moorabbin store in Victoria.

“Each warehouse has a unique piece which is what we define as a ‘wow item’,” Costco’s jewellery buyer Jennifer Cataldo told The New Daily. 

“It could be a ring, could be a pendant, could be earrings, but it’s primarily a diamond piece and they tend to hover between $300,000 and $850,000.”

The half-a-million dollar ring spotted by Ms Bechwati has actually been in the Canberra store since its 2011 launch, with Ms Cataldo admitting it had proved a hard sell given its exorbitant price.

“It’s quite difficult [to sell] … we’ve sold a lot of high-end pieces but not at that price point.”

And that’s with the Costco discount applied. Ms Cataldo confirmed the diamond carried a reduced price tag.

“We comp quite aggressively in the market so we like to see savings of a minimum value of around 20 per cent.”

https://twitter.com/jenbechwati/status/985437318227091456

Costco’s diamonds are sourced from wholesalers in the United States and the company employs a quality control team to ensure the cut, grading and metal is “correct”.

The irony of a single glistening diamond in between aisles of dustpans and baby wipes was not lost on Twitter, with many wondering how it fitted into the store’s low-price theme.

“You have to buy them in the value six pack,” one joked.

“How much is it at Aldi?” another wrote.

To shop at Costco you must be a member, with annual membership fees starting at $55.

In addition to its nine locations in New South Wales, Victoria, ACT, Queensland and South Australia, the US-based company is opening two more stores in Australia this year – one in Epping, Victoria, in August and another in Ipswich, Queensland, in November.