Shares in cryptocurrency brokerage Gemini Space Station (GEMI) jumped more than 60% after opening for public trading on Friday, before paring those gains to finish around 14% higher.

Gemini Space Station, an exchange founded by brothers Cameron and Tyler Winklevoss, opened at $37.01 after its IPO was priced at $28. It surged higher than $45 in the minutes after the stock’s public offering before falling to around $35. The midday trading price values the company at roughly $1.4 billion.

Trading was halted for 10 minutes shortly after opening on public markets following a volatility spike outside of the exchanges’ accepted limits.

The company’s IPO pricing represented an increase over an original estimate of $17 to $19, which…