The thought of a handsome, brawny sailor away at sea for a long period of time lovingly hand-crafting a personal valentine for his sweetheart back home certainly brings dreamy romantic thoughts to my mind.
It has been said that nineteenth-century sailors made wooden boxes displaying an intricate array of beautiful little sea shells they collected from remote parts of the globe while on their travels. The boxes were octagonally shaped and built of Spanish cedar or sometimes mahogany, with a hinged glass lid. Sometimes they were two boxes hinged together. Many of these valentines incorporated some sentimental message written out in tiny shells. They could be shut and locked with a key in case a love note needed to be tucked away inside. 
Ahhhh, imagine a burly sailor with Popeye forearms and strong calloused hands taking time each evening when he wasn’t on duty thoughtfully gluing the tiny seashells that he had meticulously gathered into a pleasing pattern for that special person back at home. Sometimes these patterns were further adorned with paper cutouts or bits of colored glass.
In order for a sailor to do this, he would need to carry with him things like cotton backing, colored paper -- usually pink -- glue, glass, small hinges and a list of other items. In those days, people used glue made from animal hide which would take hours to dry. Not very practical on a moving ship.
Hum. Sailors carved items like scrimshaws -- a tooth from a Sperm whale -- featuring intricate patterns of manly subject matter. There are over 100,000 species of shells found all over the world, and most of the shells used in these valentines are from the island of Barbados. It appears that many of these mementos had their origin there.In the Caribbean, Barbados was a British colony. An important call for American and English ships during the nineteenth century. The beaches were littered with seashells. There was also a gift shop.
It sold all sorts of touristy gifts such as coral necklaces, broaches, shark bone walking sticks, dried fish jaws, and tortoise shell hair accessories. Years later, when collectors were taking their valentines in for repair, conservators discovered the Barbados newspaper under the shells used for padding and support.
In reality, sailors didn't make these valentines afterall. Most were made by the people of Barbados specifically for the souvenir trade which had its heyday from the 1830s to 1880s. These boxes range anywhere in size from eight to sixteen inches in diameter. Victorians were shell-crazy. Shells were incorporated into a variety of other items including picture frames, sewing boxes, wall hangings, floral decoupage and many other keepsakes.
These mementos, especially the valentines, have gained value and popularity in the past few decades. Today, they sell regularly at Christie’s and Sotheby’s, as well as on eBay and in a few antique shops. A modest single valentine 20 years ago sold for $350 to $600. It now sells for $3,500 to $8,500, while the price for a large double valentine has jumped to between $8,500 and $18,000. In July 2006, two double octagonal sailor’s valentines went up for auction. They both well exceeded their estimates. The first had shells and dried berries. On the left it had a geometric motif of roses and a heart; and on the right side, it repeated the geometric pattern and in the center it spelled out in little shells: "For My Mother." That sold for $24,000. The second one sold also had a geometric motif on both sides. On the left it had a central motif of an anchor, and on the right a large rose at the center. It sold for $31,200.
Regardless, most of us would prefer to think of that manly sailor on his ship with a tender heart.