Guotai Junan International (01788.HK) experienced a rollercoaster trading session on Thursday, ultimately plummeting 14.59% following a period of extreme volatility. The stock's dramatic movements came in the wake of receiving regulatory approval to offer cryptocurrency trading services from the Hong Kong Securities and Futures Commission (SFC).

Early in the trading day, Guotai Junan International's stock surged nearly 90%, reaching a high of HK$7.02. This rally followed a 198% jump the previous day, reflecting investor excitement over the company's entry into the regulated digital asset space. The approval positions Guotai Junan International as one of the first traditional brokerages in Hong Kong to offer cryptocurrency trading services, including Bitcoin, Ethereum, and stablecoins.

However, the initial enthusiasm gave way to a sharp selloff as the trading session progressed. The stock's volatility may be attributed to profit-taking after the massive gains and uncertainties surrounding the implementation and potential profitability of the new cryptocurrency services. The plummet also coincided with the release of Hong Kong's "Digital Asset Development Policy Declaration 2.0," which outlines the city's vision to become a global innovation hub for digital assets. While this policy aims to boost the digital asset sector, it may have introduced short-term uncertainties that contributed to the stock's decline.