Antique Slag Lamps
Antique slag lamps are lamps that contains slag glass. Slag lamps can vary from table lamps to floor lamps or lamp shades to ceiling lamps.
History & Description
Slag glass is also commonly referred to as malachite or marble glass and is a type of opaque streaked glass. Slag glass originates from England during the late-nineteenth century. It is believed that glass manufacturers added slag from iron-smelting works to molten glass in order to create a range of inventive effects, such as tortoiseshell and marbling.
Due to the colourful and innovative effects slag glass offered, it became a popular material for lamp shades.
Guide for collectors
As a general rule, antique slag lamps sell at auction from $300 to $1,500. The most valuable and desirable examples of slag lamps are those that were produced by some of the leading glass manufacturers during the Art Nouveau period, such as Tiffany, Steuben and Roycroft. Tiffany slag lamps have sold for tens of thousands of dollars.
Collectors should proceed with caution when purchasing supposed genuine slag glass items. Today, the term slag glass is used rather casually to denote almost any type of opaque, pressed glass that contains streaks or coloured swirls.
Notable auction sales
On June 28th 2008, a Tiffany bronze and slag glass table lamp, made in the early-twentieth century, realised a price of $6,500 through Skinner Auctioneers and Appraisers in Massachusetts.
On January 9th 2010 at North Georgia Antique Auction in Dawsonville, Georgia, a rare Apollo Studios slag glass floor lamp, made by Tiffany, realised a price of $5,500.
On August 28th 2004 at Crescent City Auction Gallery in New Orleans, Louisiana, a bronze and slag glass lamp, made by Tiffany, circa 1920, realised a price of $6,750.
On September 28th 2008 at Craftsman Auctions in Lambertville, New Jersey, a Tiffany table lamp with geometric green and white slag glass realised a price of $27,000.
On January 15th 2005 at Craftsman Auctions in Lambertville, New Jersey, a Tiffany gilt-parcel table lamp in a mosaic of polychromatic slag glass realised a price of $40,000.
(All values based on auction results from Liuveauctioneers.com)