A classic and timeless look is a solitaire diamond in a prong setting. An engagement ring in this type of setting has much of the focus on the center diamond. The diamond is usually set in a 4 prong setting which can be viewed from all sides has more brilliance than any other setting, but more flaws would be visible as well. Couples will have to pay very close attention to the quality of the stone as there will be few detractors from it.
This ring is a solitaire Princess cut diamond with encrusted diamonds. It is also a very modern design with two bands near the center diamond. Keep in mind a round brilliant diamond would appear much larger if it was the same carat weight as a Princess cut.
This is mult-stone, multi-band diamond ring. Smaller diamonds are used throughout and flush mounted on the bands. The center round brilliant diamond appears somewhat larger because the small diamonds surround the center diamond making it appear larger.
The most common type of multi-stone arrangement is the 3-stone ring in a prong setting. The center diamond is matched with 2 same side diamonds that are equal or smaller in size. The smaller the side diamonds are, the larger the center diamond would appear. The standard proportion would be that the center diamond would be equal to the 2 side diamonds together in carat weight.
This 3 stone diamond ring has a synthetic blue diamond as the center stone with a matching pair of diamonds on the side. Some Tiffany branded rings also use sapphires and other jems to accentuate an engagement ring.
Tension setting is where the entire ring acts like a spring to hold the diamonds in place.
This is a picture of a 3-stone tension design, but the most common type only have one diamond.