Australian beer maker Nail Brewing revealed the secret behind its latest ale, which set a new record for the most expensive beer ever produced when it was sold at auction last month. The new limited edition brew, which was produced and sold for charity, was made from melted Antarctic ice.

Dubbed Antarctic Nail Ale, the beer first went on the auction block to raise money for the Sea Sheperd Conservation Society, an organization dedicated to protecting whales and other sealife around the globe. On November 3, a single bottle sold for an amazing $800 AUD (roughly $780), setting the new record for the worlds most expensive beer in the process. That auction was just the warm-up however, as another bottle went up for sale on November 19, smashing the new record. That second bottle sold for a whopping $1850 AUD ($1805)!

The beer was created by John Stallwood, the owner of Nail Brewing. Stallwood’s brother-in-law is part of the crew on board a Sea Sheperd ship, and recently visited an iceberg floating in the waters off Antarctica. He collected some of the ice there and flew it back to Tasmania, where it was melted and then passed on to Stallwood to use in the beer.

I’ve had some expensive beer before, but $1850 for a single bottle? I’d have to nurse that one for a really long time.