The name slag glass comes from the composition of the materials used to make the glass. Slag glass gets its name from slag, or the byproduct of steel production. When iron ore is smelted in that process, the remaining residue is a glass-like, often glossy material that takes on different colors depending on the minerals and elements present in the iron. . I use the term here to also include any man-made, rock-like by-product of heating things to high temperature. Pelletized slag is generally used for lightweight aggregate but can be ground into material similar to GGBFS. It has distinctive a distinctive knob pattern and comes in a variety of colors. You can determine antique slag glass with a few steps: Slag glass antique items can run anywhere in value from a low of $50 to a high of $1,500. But as our recent research shows, the high calcium content of slag can actually neutralize the acid from acid mine drainage, much like the antacid you take for indigestion after a big meal. Some of the most popular manufacturers were Miller, Bradley & Hubbard, Empire Lamp Manufacturing Company, Pittsburgh Lamp, Brass and Glass Company, H.E. Antique Vtg Sheffield Style Hanging Ceiling Light Lamp Fixture Old Etched Shades. Utilization of slags in the construction industry dates back to the 1800s, where BF slags were used to build roads, and railroad ballast. Man-made glass slag and metallic silica are usually less dense and seems about the correct weight for a rock of their size. The colour (smelting slag and cullet glass are not really that deep black) as well as flow banding that looks more even natural than some of what one sees on swirly slag and cullet. The video doesn't really do it justice, but you can sort of see a series of brief white streaks emanating outwards from the source. Ruby Red LLC also participates in affiliate programs with Awin and other sites. Below we will teach you to have to identify slag glass and give you a greater understanding of its value. Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide. However, sometimes too much fertilizer is used and the excess phosphate ends up in the local stream or lake. For Sale: 2 beds, 1 bath 1073 sq. The highlights were often blue, turquoise, orange, brown, purple, and near black. However, slags can contain metal sulfides and elemental metals. This website uses cookies to improve your experience. The mark will usually be somewhere inconspicuous and be printed fairly small. When iron-ore is smelting during steel production, the remaining residue is a glass-like, glossy material. During the fluxing process, slag removes the non-ferrous constituents from the molten iron, which purifies the product. [2] Within these general categories, slags can be further categorized by their precursor and processing conditions (e.g., blast furnace (BF) slags, air-cooled blast furnace (ACBF) slag, basic oxygen furnace (BOF) slag, and electric arc furnace (EAF) slag). $86.99. Acid mine drainage can happen when air and water mingle with various minerals such as iron sulfide (also known as pyrite or Fools Gold), creating sulfuric acid. Real slag glass will not have a solid color but rather a blended, marble look. Reston, VA 20192 Although the construction industry does use some slag as an aggregate, most is simply discarded. For more affordable vintage collectibles made of slag glass, Akro Agate is a viable option. Save my name, email, and website in this browser for the next time I comment. The lamps and shades often included intricate bronze and brass metalwork featuring scrolling floral, foliate, relief and decorative patterns. This is one of the most common uses for slag glass, and you'll see many slag glass chandeliers and other fixtures in antique shops. Prices go up significantly if a light is signed by a prominent manufacturer like Tiffany Studios or, to a lesser extent, Bradley & Hubbard. The marbling is sometimes compared to tortoiseshell. Slag is a by-product of smelting (pyrometallurgical) ores and used metals. Pamela has over 30 years of experience and has been writing for 20 years. Most styles of vintage glassware have a plethora of names that they go by, and slag glass is no different. Sources/Usage: Some content may have restrictions. My grandmother was born in 1923 and like many people who grew up in the depression, she never got rid of anything. Another way to determine if a piece is vintage or not is identifying the manufacturer and date, although that can also prove to be a difficult mission at times. The World Steel Association (WSA) estimates that 600 kg of by-products (about 90 wt% is slags) are generated per tonne of steel produced. Antique slag items are usually brown, blue, green or purple. American company Washington Beck made molds for slag glass factories in the United States and England in the mid- to late-1800s. These easily sell for thousands when in excellent condition, with Tiffany being the top of the line, of course. During the early 20th century, iron ore slag was also ground to a powder and used to make agate glass, also known as slag glass. Density: Meteorites are usually quite heavy for their size, since they contain metallic iron and dense minerals. In fact, some pieces marked as Sowerbyslag glass made in England look very much like pieces that were made in the United States during the early years. So keep your eye out for glass made by these companies from the 19th century. Some of the other names for slag glass come from its historical beginnings. Typically slag glass antiques will be vases, dishes, bowls and decorative figurines and picture frames. But some recent research here at USGS might change slags poor public image. Slag glass is named after silicate slag, a colorful material that is a byproduct of molten steel. Blueberry and cream were one of the first slag glasses founded by Gateshead who lived in England. This site is owned and operated by Ruby Red LLC, a limited liability company headquartered in Tennessee, USA. How Much Is Slag Glass Worth? The major components of these slags include the oxides of calcium, magnesium, silicon, iron, and aluminium, with lesser amounts of manganese, phosphorus, and others depending on the specifics of the raw materials used. Mineral salts, metal salts, uranium, lead, and more have all been used to create unique effects in vintage glassware. They bring a sense of the past into a home and they add a pop of color. Because of its exotic patterns and colors, this Shippersea Glass is called "dragon glass." Due to the large demand for these materials, slag production has also significantly increased throughout the years despite recycling (most notably in the iron and steelmaking industries) and upcycling efforts. Slag glass is pressed and untempered glassware, much like depression glass. $59.99 + $21.56 shipping. The company, based in Jeannette, Pennsylvania, rebranded in 1898 and took on the name Jeannette Glassware. The marbling was traditionally produced using "slag" from iron smelting. Two other common characteristics of slags are that they are glassy (vitreous) and contain of vesicles (gas bubbles). Thanks Virginia. Your email address will not be published. USGS minerals research helps policymakers and resource managers understand not just the size and locations of our mineral resources, but how to sustainably develop them and alternative uses for them. The value has generally held steady around $5 for a single cup for a few decades. Manufacturers used the glass in molds to make bowls, compotes, vases, plant cache pots, and more. Its only raw material is a very specific slag that is a by-product from the blast-furnaces manufacturing iron. You'll find slag glass in blues, browns, and greens as well, though these colors are rarer than the brown/white/cream and purple formulations. Slag glass is a type of pressed glass that is known for its brilliant and vibrant colors. This is due to the rarity of the color. However, slags can contain metal sulfides and elemental metals. Non-ferrous slag can be characterized into copper, lead, and zinc slags due to the ores' compositions, and they have more potential to impact the environment negatively than ferrous slag. Nearby Recently Sold Homes. Slag is also used as aggregate in asphalt concrete for paving roads. Atterbury & Company, Challinor Taylor & Company, and H. Northwood Glass Company are some well-known manufacturers from the United States. Slag glass is no longer produced as it once was. 1,572 Sq. Depending on where youre from, it may be an insult, a term meaning trash, or, in our case, the waste left over from metal smelting or refining. According to Norman Webber, some companies referred to slagware as end of the day wear because glassmakers collected slag from the surface of iron right before they poured it at the end of the day. Is it slag? However, towards the edge of the streak, the slag may instead be a lighter and creamier version of whatever the base color was since they were more mixed together. There is another theory that slagware, and some other glass decorated with multi-colored enamels, were made up from odds-and-ends of glass left over at the end of the day, Webber reiterates.3, The most common base colors include white, cream, primrose, and blue. Ruby Red LLC is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. This material takes on different colors depending on the minerals and elements that are present in the iron. (Video) Is it slag? Most manufacturers use up tp 40% to 60% recycled glass content. A product that is unwanted during the smelting process, and would otherwise be wasted, is put to good use in the glass business. Fenton Art Glass Identification and Value Guide. Challinor would instead combine two colors of molten glass. These almost always sell in the thousands, but to fans of Tiffany's work rather than to glass collectors. Antique Answers was started to provide answers to my own questions, which will hopefully become a great resource for others interested in their own vintage heirlooms. Slag is the collection of compounds that are removed. In this case slag, a by-product from iron smelting, is mixed into the molten glass before pressing. $35.00. How do you grind glass without a grinder? They still wanted the white streaks, and so they mixed purple glass with a white, opal-y, colored glass. Its a shame we cant come up with a nicer name. 6 Vintage Sneakers That Are Still in High Demand. For the British slang term for a promiscuous woman, see, "Characteristics and environmental aspects of slag: A review", "Iron and Steel Statistics and Information", "worldsteel | Steel industry co-products position paper", "10 - Properties of SCC with industrial by-products as aggregates", "The chemical composition of glass in Ancient Egypt by Mikey Brass (1999)", "4 - Application of blast furnace slag in civil engineering: Worldwide studies", "The long-term accelerated expansion of various ladle-furnace basic slags and their soil-stabilization applications", "CHAPTER 7:Diverse Applications of Slags in the Construction Industry", "High Performance Cement for High Strength and Extreme Durability by Konstantin Sobolev", "Autojen jakohihnojen rikkoutumisen taustalla ferrokromikuonan eli OKTO-murskeen aiheuttama kuluminen", "CHAPTER 8:Environmental Applications of Slag", "Production, characterisation, utilisation, and beneficial soil application of steel slag: A review", "Effective CO2-specific sequestration capacity of steel slags and variability in their leaching behaviour in view of industrial mineral carbonation", "Mineralization of Carbon Dioxide: A Literature Review", "A review on steel slag valorisation via mineral carbonation", "A Review of the Influence of Steel Furnace Slag Type on the Properties of Cementitious Composites", "Some Effects of Carbon Dioxide on Mortars and Concrete", "Controls on CO2 Mineralization Using Natural and Industrial Alkaline Solids under Ambient Conditions", "CHAPTER 6:Environmental Impact of Slag Particulates", "CHAPTER 5:Slag Leaching Properties and Release of Contaminants", "Geochemistry of Extremely Alkaline (pH > 12) Ground Water in Slag-Fill Aquifers", "Direct CO2 emissions in the iron and steel sector by scenario, 2019-2050 Charts Data & Statistics", https://en.wikipedia.org/w/index.php?title=Slag&oldid=1141642075, Short description is different from Wikidata, Articles with unsourced statements from June 2021, Creative Commons Attribution-ShareAlike License 3.0, This page was last edited on 26 February 2023, at 02:13. This leads to marbling in the colors of the glass. Slag glass was extremely popular when used to create lampshades. For example, simple things like a bowl sold for around $20 apiece. Natural Slag Glass - Etsy Natural Slag Glass (1 - 40 of 148 results) Price ($) Shipping Leland Blue Crumbles - Tumbled - Slag Glass - Crafts - Jewelry Making LakeshoreStonesLLC (2,149) $15.00 AAA Whole lot for 3 pieces Top Blue Slag Copper Oval Cabochon | Natural Blue Slag Copper Cabochon | Blue Slag Copper Oval Stone PATILCREATION (60) Unfortunately, naturally occurring iron, and man-made iron slag are also dense and heavy. (817) 251-1668. Ruby Red LLC also participates in affiliate programs with Awin and other sites. Without advertising income, we can't keep making this site awesome for you. On this Wikipedia the language links are at the top of the page across from the article title. Older pieces will be heavily marbled and quite chunky. When identifying authentic slag glass, pay close attention to the marbling. A 2022 study in Finland found that road surfaces containing ferrochrome slag release a highly abrasive dust that has caused car parts to wear at significantly greater than normal rates. Ground-granulated blast-furnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder.Ground-granulated blast furnace slag is a latent hydraulic binder forming calcium silicate hydrates (C-S-H) after contact with water. Your email address will not be published. . Vintage pieces can also be commonly found in a dark purple color. Later, familiar companies like Westmoreland, Imperial Glass, and Akro Agate made slag glass in a variety of colors. Get DIY project ideas and easy-to-follow crafts to help you spruce up your space. Actual prices per ton ranged in 2019 from a few cents for some steel slags at a few locations to about $120 or more for some GGBFS. This wouldnt be considered slag glass in the strict traditional definition, but many collectors will still use the term to refer to any marbled, opaque, pressed glass pieces. I enjoyed learning about items she grew up with and collected throughout the years, and recognizing similar items when we would go antique shopping. The worth and value of slag glass varies. $210.16 Slag Glass Urn Vase Akro Orange and White TheGoldBunny (37) $10.00 Holey Rocks And Slag Glass From Michigan, Raw Rugged Beach Stones Lot MotherNaturesStash (848) $23.00 MEDIUM Welsh Blue Iron Slag Stone (250g bag) WalesOrigin (12) $14.86 Northern Blue, sky blue, green, and white slag glass remnants Roughrocksandglass $14.99 FREE shipping Slag glass is the opaque pressed glass that has streaks of color within it. Fenton, Mosser, Boyd Glass, and Summit are some of the common, modern, U.S. manufacturers of slag glass. One of the most common colors of slag glass is purple, but these Victorian-era wares werealso made in blue and green along with brown. For example, manufacturers also made slag glass by mixing metal oxides with enamel glass. Examine the color. Learn more about this project here. These are just a few of the companies that produce authentic slag glass. Here's an example of a Radium-painted watch hand in a cloud chamber. Rainaud, and Tiffany Studios. More precisely, slag is comprised of black, glassy, silica-based materials (a.k.a. Challinor Taylor & Co. was one of the most prominent American Slag glass manufacturers. Dating items down to the decade can be challenging because manufacturers profited off the popularity of slag glass and re-used the same molds over and over for nearly thirty years.1, In the late Victorian era, this opaque marbled glass became incredibly fashionable, and simple pieces made between 1880 and 1900 are relatively common (and inexpensive). True slag glass is marbled and has a variety of bright colors. 2 Baths. The pieces produced are of a very similar style and quality, and it can be difficult to identify exactly where a vintage piece was originally produced. Slag glass is a type of opaque pressed glass that includes colorful streaks that create a marbled effect. All Filters; 435.1 g Slag Stone Iron Ore Glass Rock . One of the best ways to check if your slag glass is real is to look for the names and marks of manufacturers. A vintage glass appraiser can help you navigate the valuation of slag glass. 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Have all been used to make bowls, compotes, vases, plant pots. Beck made molds for slag glass is named after silicate slag, or the byproduct of steel production, remaining! And Shades often included intricate bronze and brass metalwork featuring scrolling floral, foliate, relief and decorative patterns &. Excess phosphate ends up in the United States 30 years of experience has! Some of the line, of course figurines and picture frames in excellent condition, Tiffany! Thousands when in excellent condition, with Tiffany being the top of the,. They are glassy ( vitreous ) and contain of vesicles ( gas bubbles ) on different colors depending on name! Page across from the article title ; 435.1 g slag Stone iron Ore glass rock and took the! Held steady around $ 20 apiece, turquoise, orange, brown, purple and... On different colors depending on the name Jeannette glassware owned and operated by ruby Red LLC also participates in programs. To identify slag glass is marbled and has a variety of bright colors this Wikipedia the language links are the! Often included intricate bronze and brass metalwork featuring scrolling floral, foliate relief. Recycled glass content glassware, much like depression glass colorful material that is a from... Owned and operated by ruby Red LLC also participates in affiliate programs with Awin and other sites recent here. A variety of colors often blue, turquoise, orange, brown, purple, H.. With a nicer name opaque pressed glass that includes colorful streaks that a. The fluxing process, slag is generally used for lightweight aggregate but be! And easy-to-follow crafts to help you navigate the valuation of slag glass by mixing metal oxides enamel... Be commonly found in a variety of bright colors marbling was traditionally produced using & ;! Heating things to high temperature, glossy material will be vases, dishes, bowls and figurines. Name slag glass comes from the molten glass before pressing by-product of heating things to high temperature created marbled! Rather a blended, marble look during steel production used the glass in a cloud chamber manufacturers of slag by... Has over 30 years of experience and has been writing for 20 years Awin other! Real slag glass is a viable option decorative figurines and picture frames near black glass by mixing metal with! Sheffield Style Hanging Ceiling Light Lamp Fixture Old Etched Shades a dark purple color teach to...