Butterfield Preferred shares dropped $10 (.81 percent) on the Bermuda Stock Exchange yesterday, trading 254 shares to close at $1220.Butterfield Bank gained one cent (.81 percent) trading 22,879 shares to close at $1.24.Overall, the BSX closed at 1,068.70, up 4.74 points (.45 percent), trading 22,879 shares worth BD$28,369.96 and 254 US shares worth US$316,556.89.