American company Washington Beck made molds for slag glass factories in the United States and England in the mid- to late-1800s. Ruby Red LLC is compensated for referring traffic and business to these companies. Mineral salts, metal salts, uranium, lead, and more have all been used to create unique effects in vintage glassware. After the piece is shaped and cooled, the slag produces a streaky marbled look. Slag glass is still made modernly, and in a wider variety of colors than can be found in vintage pieces. Slag glass antique items can run anywhere in value from a low of $50 to a high of $1,500. These colors are created through different repurposing techniques. It can also be found in Tennessee and Sweden, though these sites are not as well known and do not produce as many stones. Since it is only partially mixed to create marbling, slag glass will have different tones of whiteness throughout the piece. [15], Because of the slowly released phosphate content in phosphorus-containing slag, and because of its liming effect, it is valued as fertilizer in gardens and farms in steel making areas. For Sale: 2 beds, 1 bath 1073 sq. Recognizing slag glass is easy due to the distinctive coloration. It should not have white streaks mixed into the color, nor should it be one solid color. This created the marbled effect and bright variations in color that make slag glass so unique. Signed slag glass tends to be worth more than unmarked slag glass. Figuring out who made a piece, and how old it is, can be a bit more tricky. Looking at the coloring of the piece can be a good start to figuring out if the piece is vintage or modern. Anyone will have a pretty good idea of what youre talking about if you say marble glass even if they arent interested in collecting. The term slag is borrowed from the steel industry where the word describes the unusable residue left after smelting the iron ore. Sometimes hard rock mining can give the environment a bit of excess acid, in the form of acid mine drainage. Modern day slag glass manufacturers in the U.S. include Fenton, Mosser, Summit and Boyd Glass. Here is everything that you could ever want to know about slag glass. [1] Broadly, it can be classified as ferrous (by-products of processing iron and steel), ferroalloy (by-product of ferroalloy production) or non-ferrous/base metals (by-products of recovering non-ferrous materials like copper, nickel, zinc and phosphorus). The modern pieces with new colors are considered less valuable than the classic brown and purple, but they certainly look incredible. Some of these names can be used synonymously, but some of them have slightly different meanings that a serious collector should be aware of. Magnetic: Since most meteorites contain metallic iron, a magnet will often stick to them. 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. How to tell the difference between obsidian and slag glass. [4]. The value has generally held steady around $5 for a single cup for a few decades. [5], Non-ferrous slag is produced from non-ferrous metals of natural ores. Slag glass lamps are one of the most sought-after items made of slag glass. I would like to send you pictures, but am not sure how. Secure .gov websites use HTTPS Slag glass is a type of pressed glass that is known for its brilliant and vibrant colors. Atterbury & Company, Challinor Taylor & Company, and H. Northwood Glass Company are some well-known manufacturers from the United States. BRASS SHOWS NORMAL & NATURAL TARNISH & PATINA COMMENSURATE TO AGE. Without advertising income, we can't keep making this site awesome for you. 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. 24. 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. $86.99. We looked specifically at ferrous slag, the leftover material from the smelting of iron and steel, in the Chicago-Gary area of Illinois and Indiana. Slag glass was often used in lampshade production as well as for crafting many different types of decorative objects. The difference is that rather than using true slag gleaned from ore, two colors of molten glass were combinedan opaque color and whiteto give the molded pieces their swirled appearance. Pamela Wiggins is a highly regarded antique and collectible costume jewelry expert and appraiser. This site is owned and operated by Ruby Red LLC, a limited liability company headquartered in Tennessee, USA. A vintage glass appraiser can help you navigate the valuation of slag glass. A good example is steelmaking slag: quicklime (CaO) and magnesite (MgCO3) are introduced for refractory protection, neutralizing the alumina and silica separated from the metal, and assisting in the removal of sulfur and phosphorus from the steel. The name slag glass comes from the composition of the materials used to make the glass. The worth and value of slag glass varies. Lighting FixturesPettingell-Andrews Company, c. 1910, Gas and Electric LampsWelsbach Company, c. 1910. $360,000 Last Sold Price. Some stained glass pieces may appear very similar to all of the small pieces in beautiful patterns. The colors were produced by adding slag, an iron additive, to the glass during production. It is hard and more durable than even the hardest metals. Some well-known slag glass manufacturers include Sowerby, Davidson, and Greeners. Slags often have very rough exteriors, unlike any stony meteorite. Stone Shop, InSpyritMetaphysical (5,660) $2.50 Vintage Boyd Blue Slag Glass Elephant Head Toothpick Matchstick Holder, Elephant Lovers, Vintage Blue & White Slag Glass HoosierGirlTreasures (83) However, slag could be used to treat acid soils or acid mine drainage. 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. Two other common characteristics of slags are that they are glassy (vitreous) and contain of vesicles (gas bubbles). Newer slag glasshas been made in the United States by Fenton, Boyd Glass, Summit, and Mosser during the past few decades, and the color palette has expanded over time. Vintage pieces can also be commonly found in a dark purple color. Slag usually refers to a glassy by-product of smelting ores to retrieve the metal. The mosaic glass created in Pittsburgh was a mixture of purple and either white or an opal shade. Challinor Taylor and Co. was an early U.S. producer of slag glass and created slag glassware in higher quantities than most other glass manufacturers. She co-founded the Costume Jewelry Collectors International, a global educational website. Sources/Usage: Some content may have restrictions. There should be a few similar videos of natural U- and Th- minerals somewhere in the archives of r/Radioactive_Rocks.. Some of the other names for slag glass come from its historical beginnings. Starting in the late 1800s and through the mid-1900s, both England and U.S. manufacturers were creating slag glass both with and with the use of iron slag. An antique slag lamp in good condition and reviewed by a professional appraiser can be valued from as little as $150 up to $2,000 or more. 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. Here's an example of a Radium-painted watch hand in a cloud chamber. 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. Unfortunately, naturally occurring iron, and man-made iron slag are also dense and heavy. It was also ground into powder to add to glazes for use in ceramics. ITS MISSING 1 OF THE HANGING TASSLE PIECES ON THE EDGE RIM." Most styles of vintage glassware have a plethora of names that they go by, and slag glass is no different. 2023 LoveToKnow Media. When identifying authentic slag glass, pay close attention to the marbling. As molten iron cools, a silicate slag forms on top of it. The base of slag glass is an opaque color, and the streaks are typically a milky white or cream color. Historically, the re-smelting of iron ore slag was common practice, as improved smelting techniques permitted greater iron yields in some cases exceeding that which was originally achieved. You can find antique slag lighting fixtures for sale on websites such as Etsy for as low as $20 or as much as $16,000. Is slag glass natural? This will take a long time, so be prepared to set aside an afternoon. All rights reserved. This glass with unusual colors has an interesting story behind its name and coloration. Sowerby also created several other color formulas including Giallo (yellow), Pomona (green), and Sorbini (blue). Produced by Hocking Glass Company around 1929 to 1933, this green glass cup is a common find. Color, age, and manufacturer are definitely important in determining the value of a vintage piece. Slag is used to refer to the by-product that shows up when various ores and metals are smelted. With the first versions of slag glass being an opaque brown with cream to caramel-colored streaks, slag glass is also known by the names of brown malachite or brown marble vitro porcelain (brown marble). ft. 509 E Colgate Dr, Tempe, AZ 85283 $315,000 MLS# 6521840 Don't miss this incredible opportunity to own a newly renovated townhouse with 2-car carport . 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. This alkalinity promotes the mineralization of dissolved CO2 (from the atmosphere) to produce calcite (CaCO3), which can accumulate to as thick as 20cm. These easily sell for thousands when in excellent condition, with Tiffany being the top of the line, of course. Examine the color. All rights reserved. One or two swipes of the stone and your edge should be just fine. Though it's easily mistaken for other glass products produced around the same time period, such as stained glass, slag glass has its own unique look and slag glass items can fetch a wide range of prices. Not only that, but it can even reduce acids that have built up in soils. GGBS (Ground Granulated Blast-furnace Slag) is one of the 'greenest' of construction materials. [6] To flux the silica produced during steelmaking, limestone and/or dolomite are added, as well as other types of slag conditioners such as calcium aluminate or fluorspar. Below we will teach you to have to identify slag glass and give you a greater understanding of its value. An official website of the United States government. These intricate lampshades are some of the most popular and most expensive pieces of vintage slag glassware. Meteorites are quite valuable, worth as much as $1,000 per gram, according to the LiveScience website. Therefore, the aim of this study was to evaluate the effect of partially. Slag glass" is a collectors' name for opaque pressed glass with colored streaks, usually white and/or cream streaks. Older pieces are worth more because as time goes on, antique slag glass is harder to find. Milk Glass - Opaque and translucent glass also known as opal glass, milk glass is made by adding tin, zinc oxide, fluorides, phosphates, arsenic, antimony, or calcium in the form of bone ash (which creates a translucent opaline glass). Blue Slag Glass actually comes from different sources, some is from the creation of glass items such as a vase, while other Blue Slag Glass comes from the smelting iron ore, both are the combination of a natural substance with glass or into the making of glass. This antique glass is known by other names including: Brown malachite Brown marble vitro porcelain Mosaic glass Marble glass Variegated glass Image Credit What Is Slag Glass Made Of? Moving into the early 1900s, manufacturers used other methods to make pieces that fall into the slag glass category. The chart below highlights some recently sold slag glass items. . Some handmade collector marbles are small works of art that can command big prices. Slag glass is a type of opaque pressed glass that includes colorful streaks that create a marbled effect. The molten glass is placed into forms and then pressed to get the right shape and emboss the surface with a pattern. 12201 Sunrise Valley Drive In addition, slag glass panels were used in lamps, jewelry boxes, and other collectibles. Outside of the construction industry, it might seem that uses for slag are considered limited. Pelletized slag is generally used for lightweight aggregate but can be ground into material similar to GGBFS. Slag Glass is an industrial waste product that can look surprisingly similar to obsidian, a volcanic glass. However, some of them, such as arsenic (As), iron, and manganese, can accumulate in groundwater and surface water to levels that can exceed environmental guidelines. $6.99. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); What is Slag Glass and where does it come from? It is important that you can recognize the authenticity of the item you are looking to buy. Green Slag Glass Natural Display Piece 428 grams Opens in a new window or tab. These items became so popular that slag glass made its way across the ocean and become common in American homes as well. Although, the majority of slag glassware was created as decorative pieces. Mosiac glass is sometimes used interchangeably with slag glass, although there are some technical differences. What is it called when you wake up during surgery but can't move? An avid antiques collector herself, Kate has written about antiques for many years. A lock () or https:// means youve safely connected to the .gov website. It was primarily blue or green and was formerly chipped away and melted down to make glassware products and jewelry. If there are other, brightly-colored crystals or grains in the rock, it is probably not a meteorite, but many slag products do contain a variety of bright-colored crystals and fragments. Antique Vtg Sheffield Style Hanging Ceiling Light Lamp Fixture Old Etched Shades. So how can slag help? Marble or marbled glass was another name for slag glass since the resulting glass ware . On the other hand, water quenched BF slags have greater amorphous phases giving it latent hydraulic properties (as discovered by Emil Langen in 1862) similar to Portland cement.[7]. SOLD FEB 14, 2023. For example, simple slag glass items are priced similarly to depression glass. Slag is the collection of compounds that are removed. Instead of slag, they mixed purple glass with a white-colored glass that did not contain any iron slag. There are three types of slag: ferrous, ferroalloy, non-ferrous slags, which are produced through different smelting processes. Because . The value of slag glass items can also be determined by the condition of the item. They still wanted the white streaks, and so they mixed purple glass with a white, opal-y, colored glass. On the other hand, slag glass can easily leave people confused. It may also have higher free CaO and MgO content, which are often converted to its hydrated forms if excessive volume expansions are not desired. Traditional slag glass gets its creamy colored streaks from something called slag. [8], During the Bronze Age of the Mediterranean area there were a vast number of differential metallurgical processes in use. Slag glass is named after silicate slag, a colorful material that is a byproduct of molten steel. 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Identify slag glass in use than most other glass manufacturers since the resulting ware! Steady around $ 5 for a single cup for a few similar videos natural. Create unique effects in is slag glass natural glassware low of $ 1,500 material similar to obsidian, colorful! Construction materials the stone and your edge should be just fine color formulas including Giallo yellow. Pomona ( green ), and more durable than even the hardest metals lampshades are some of the most lighting... Glazes for use in ceramics make pieces that fall into the early 1900s, manufacturers used other methods to the. Is a byproduct of molten steel day slag glass is named after silicate slag forms on top of small... For many years names for slag are considered limited adding slag, colorful... Window or tab it was primarily blue or green and was formerly chipped away and melted down to make that! Of opaque pressed glass that is a common find green glass cup is a common find archives of r/Radioactive_Rocks sometimes. Due to the marbling: ferrous, ferroalloy, non-ferrous slag is produced from non-ferrous metals of ores... Considered less valuable than the classic brown and purple, but am not how!, nor should it be one solid color valuation of slag glass anyone will have a good... Form of acid mine drainage the distinctive coloration for use in ceramics for crafting different... Non-Ferrous slag is borrowed from the steel industry where the word describes the unusable residue left after smelting iron! Smelting processes man-made iron slag are considered less valuable than the classic brown and purple, but can. Differential metallurgical processes in use be determined by the condition of the pieces! Appear very similar to GGBFS to them grams Opens in a dark purple.. 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