Valentine's Day has been celebrated for centuries. By the 1790s, romantic cards were being given to that "special" person. The idea of cards and gifts has continued, and collectors search for all types of valentines of the past - everything from pasted-together lacy cards and "mechanical" cards that pop open into a 3-D display, to very modern talking cards. Sometimes collectors think any picture or figure with a romantic message is an old valentine. One of the most famous of these is the "sailor's valentine." It usually is an octagonal wooden box that holds a picture made of seashells placed in a geometric pattern. Often the design included sentimental words like "Love the Giver" or "Forget Me Not." For many years, collectors thought these boxes were made by sailors on long voyages as gifts for a girlfriend or mother. They were considered nautical folk art in a category with carved whales' teeth and other scrimshaw. They were expensive, selling for about $200 to $500. In the 1970s, a sailor's valentine was discovered that had a label on the back: "B.H. Belgrave, Dealer in Marine Specimens ... Bridgetown, Barbados." There was even a crushed Barbados newspaper under the shells. Further research showed that the shells were from local waters and some of the boxes had slogans that were not romantic. It was determined that the boxes were sold to sailors who visited Barbados and took them home as souvenirs. The name "sailor's valentine" continues to be used, though, and folk art collectors still pay high prices for old examples. San Rafael Auction Gallery in California sold a 19th-century example in 2011 for $1,800. It had a heart in the center formed by shells. Copies of these shell pictures made today sell for about $500 to $2,500. There are also companies that sell the shells, boxes and other parts needed to make your own new sailor's valentine.