Click to view a price quote on GM. : Bitcoin posted additional gains on Tuesday, narrowing losses sustained the previous week and heading toward surpassing its previous record highs as investors continued to bet the world’s biggest digital currency is worth more than the market value of Apple  (AAPL) - Get Report, General Motors  (GM) - Get Report and even Tesla  (TSLA) - Get Report. Bitcoin was up another 2.45% at $54,889, according to CoinDesk. The digital asset set a record of $64,829 earlier this month.