This style of engagement ring is incredibly popular. Just like classic solitaire, this incredibly popular style of engagement ring can be done in ant color of metal and with any shape of center diamond.
Diamonds can go halfway around the band, two-thirds or all the way around the band. Keep in mind, if you make an eternity band, it cannot be resized like a normal ring because each small diamond is custom fit and sized for the ring.
Because of that, if you resize the ring, you might end up needed to remake it. Bear that in mind as you create the design for your ring. Diamonds halfway around the band or two-thirds of the way down is a less-expensive and more economical option.