Today, cards, usually not sent from Tower dungeons these days, form one of the most popular messages with an estimated one billion sent each year.

Mass-produced valentines found their way to the marketplace in the late 1830s with most of them produced in Europe. By the middle of the 19th century, crimson hearts, colorful roses and Cupid with his bow and arrow gained popularity with valentine producers.

During the 1870s, George C. Whitney developed domestic material and the equipment needed for fancy embossing. Before this introduction, most paper lace was imported. About 20 years later, valentines saw more ingenuity in their creation.

Stand-up cards with a base and several three- dimensional fold-out layers were popular from about 1895 until 1915 as were honeycomb paper puffs which opened to form bells, fans, balls, hearts and other shapes. And, because they could be mailed flat and then easily folded out by the receiving party, they became a great fad.

Mechanical valentines also came into vogue during this time. Featuring automoblies, ships and trains with moving parts, a paper lever would send these cards into motion.

And, just like there are old postcards for every holiday on the calendar, there are also antique Valentine postcards out there. Unfortunately, and probably because the two aforementioned varieties were so popular, these don't have as much value.

Not that long ago the beginning collector could find shoe boxes full of old or older valentines at estate or garage sales. Unfortunately, the popularity of victorian decorating and the increasing interest in vintage Valentines has made such a find more uncommon.

However, if you build a small collection of these Valentines one card at a time, you'll end up with a special collection to display each year.

There are many books on the market that can help you identify and find price values for old Valentines. A trip through a good flea market or antique store also can shed some light, since most dealers are generally fair with their prices. It's also fun to read about the history of these loving tributes.