Bitcoin was recently trading at about $21,100, a more than 5% increase over the past 24 hours that helped the largest cryptocurrency regain much of the ground lost the previous day. Ether, the second-largest crypto by market cap, was changing hands at over $1,140, an 8% gain. Other major altcoins assumed various shades of green with STORJ and POLY assuming two of the darkest hues, rising more than 30% and 20%, respectively at one point.