Cameron and Tyler Winklevoss's Gemini Trust Company LLC has gotten a New York State regulator's blessing to trade another kind of cryptocurrency on its bitcoin exchange.

Gemini won approval from the New York Department of Financial Services to begin trading Ether, a cryptocurrency similar to bitcoin, on its platform immediately, according to a release Thursday. The twins, who claimed that Mark Zuckerberg stole their idea for a social-networking website when he started Facebook Inc., were early entrepreneurs in the bitcoin industry.

With the agency's approval, Gemini is expanding the kinds of cryptocurrency that can trade on its platform. Similar to bitcoin, Ether is based on a distributed ledger called blockchain. 

"Their approval of Gemini as the first-ever licensed platform to support Ether trading demonstrates their commitment to being global thought leaders in financial regulation that both protects consumers and fosters innovation," the Winklevoss brothers said in the statement.

Gemini Trust first received state approval to start a bitcoin exchange in October, allowing users to convert virtual money to U.S. dollars and vice versa. It was the second bitcoin company to be designated by the state agency as a trust after ItBit Trust Co. got approval last year.