Victorian glass is highly collectible. From everyday flower vases to exquisite art glass, the Victorian era has much to offer the antique glass enthusiast. If you want to learn how to identify authentic Victorian glass and estimate its value, its helpful to be familiar with the registration markings you might expect to find on genuine pieces.

The Victorian Glass Registration Lozenge, or “Diamond Mark” as it is sometimes called, is stamped on to every piece of glass that was manufactured and registered in England between the years of 1842 and 1883. If you know how to read the mark, you can decipher the date the item was made as well as the identity of the manufacturer.

The mark is basically a diamond shape with an oval perched on top of the top point of the diamond. Each corner of the diamond is marked off with a curved line, and either a number or a letter is found in each of these little corner pockets of the diamond. These letters and numbers indicate month, day, year, and parcel associated with the glass design.

The positioning of these letters changed in 1868. From 1842 through 1867, a letter in the top corner of the diamond indicated the year, a number in the diamond's eastern corner indicated the day, a number in the bottom corner indicated the parcel, and a letter in the diamond's western corner indicated the month of the registration. In 1868, however, day switched positions with year and parcel switched positions with month. If your Victorian glass has a number in the top point of the diamond rather than a letter, you'll know that the piece was made after 1867.

All this might sound a little complicated, but don't despair. Now that you know the basics, identifying your specific piece of Victorian glass is easy. There's a very useful website that provides a handy tool for translating the Victorian Glass Diamond Mark—check out the link below, and get ready to find out exactly how old your Victorian glass is and discover who made it.