“Not In A Silver Casket Cool With Pearls” concerns itself with romantic love, a subject often explored in sonnet form. However, Edna St. Vincent Millay introduces her subject with an image that many would consider highly unromantic—a casket. In addition, the speaker begins in the negative, announcing how things won’t be, and therefore establishing a kind of authority. It is a “silver casket” (Line 1). The metallic nature of the material lowers the heat before the reader even arrives at the “cool pearls” (Line 1). Even with the further embellishment of rubies and sapphires—“red corundum or with blue” (Line 2), the container is useless, “(l)ocked” (Line 3) as it is and with “the key withheld” (Line3). The speaker will not be the keeper of such a safe, beautiful though it may be, and the choice of “other girls” (Line 3), who, unlike the speaker, keep their precious love in reserve and safely out of reach.

Though the “lovers’-knot” (Line 5) and a “ring” (Line 5) often signify commitment, the speaker views these symbols as trappings. To her, these things are constructed to enforce a coerced faithfulness—“Semper fidelis” (Line 7), Latin for aways faithful, and a motto for the US Marines, as well as other martial entities.