LONDON—Bitcoin on Tuesday held ground just below its highest this year, touched a day earlier, with gains for the original cryptocurrency topping 27 percent since the Ukraine war. Bitcoin hit $48,234 on Monday evening, its highest since Dec. 31. It was last trading up 0.9 percent at $47,553. Its gains lifted smaller cryptocurrencies that tend to move in tandem with bitcoin. Ether, the second biggest token, hit $3,436 on Monday, its highest since early January. Market players cited emerging signs of a new wave of adoption of crypto by institutional investors and financial firms, whose interest over the past two years has fuelled crypto’s journey to mainstream asset from niche technology. Bitcoin has risen over 12 percent in the last week alone. Though bitcoin and other cryptocurrencies are now spoken of in the same breath as traditional assets from stocks and foreign exchange to bonds, its remains as volatile as …