The emerald has a larger, open table (top section), so clarity is very important. If you do choose an emerald with a lower clarity grade, such as SI, review the clarity plot on the diamond certificate. The emerald cut is different due to its pavilion (bottom portion of the diamond), which has rectangular facets, giving the diamond a unique optical appearance. The length to width ratio of an emerald diamond will determine how it looks from the top. The most traditional emerald diamonds have length to width ratios between 1.3 and 1.4.