On bottom: 19-kt yellow-gold Gothic Collection band with milgrain detail, $1,700, Scott Kay, scottkay.com. From left: Channel-set raw-diamond band set in 18k yellow-gold fused to sterling-silver band, $2,200, Todd Reed, clay-pot.com. Platinum In-gauge Collection band with black enamel filler, $2,300, Verragio, verragio.com. 24-kt pure gold Tiramisu band, $1,460, Gurhan, gurhan.com. Platinum band, $2,450, Ritani, ritani.com.