Wallet Card with the last opal glass sign in Manhattan

From the 1910s to the 1930s, opal glass signs were a popular way to make lit-up signs for a business. They were made with translucent glass backlit with light bulbs inside the sign.  Eventually the popularity of neon by the late 1920s spelled the end of opal glass signs. According to New York Neon, this sign for Barbetta Restaurant is the last remaining opal glass sign in Manhattan.