Instructions
Read about the history of jewelry to familiarize yourself with the various periods. Some of the periods are named after British monarchs including Georgian, Victorian and Edwardian. Others get their names from the cultural aspects of the time such as Art Nouveau, Art Deco and Retro. Antique Jewelry Online has a historical view of antique jewelry by time frame. See the Resources section below for a link.
Confirm the material from which your piece is crafted. Different metals came into use at different times, which helps determine the date of your jewelry. The very strong metal platinum, for example, appeared in the late 1800s but was banned from jewelry use during World War II. This information will rule out the Georgian, early Victorian and Retro periods. Your jewelry may have markings of the materials used such as "Plat." for platinum or "Ster." for sterling silver.
Measure the length of your necklaces or earrings. Following the clothing styles of the times, nineteenth century necklaces tended to be short to set off a low neckline. Early twentieth century necklaces and earrings tended to be longer, especially during the "flapper" period of the 1920s.
Look at motifs or depictions of scenes on your item. Nature and sentimental motifs of flowers, hearts and animals were popular during Queen Victoria's reign (1837 to 1901) while Cubism-inspired geometric shapes were popular during the Art Deco period (1920 to 1935).
Determine what stones are used in your jewelry. Early pieces from the eighteenth and nineteenth centuries used classic cuts of diamonds, garnet and amethyst. Later pieces from the early-to-mid-twentieth century added a range of semi-precious stones such as opals, pearls and rubies, both natural and synthetic.
Look for any manufacturer's markings, engravings or signatures. Matching a maker to a time period will help you accurately date your jewelry.
Bring your item to an antique jewelry appraiser or dealer if you want a more detailed dating of your piece. Tell him all that you have learned about your jewelry. He may be able to narrow down the dating.