Orange sea glass from original orange glass, not golden amber or Amberina, is the most rare of all. Several glass manufacturers (Jeanette, Federal, Fire-King, and Imperial) made translucent orange tableware they called ‘’iridescent’’ in the early 1900s, and its pieces are still possible to find. Intensely iridescent ‘’Carnival glass’’ was also made in orange at that time by exposing the glass to heated metallic vapors that left a distinct rainbow effect on the glass surface.
Some sea-glass hunters have been lucky enough to find red, the most coveted of all sea-glass colors. Most pieces of red are likely from Victorian lamps and lanterns, discarded stained glass layered or ‘’flashed glass’’ tableware, various pieces of Depression glass, automobile brake lights, and marine lights. Though other colors may arguably be more attractive, most collectors of sea-glass consider red their Holy Grail. A very limited amount of red glass has been mass-produced in the last 50 years, so one can make assumptions about its age. Some people have found pieces old Schlitz beer bottles in a deep ruby-red color resembling maroon. The color was called ‘’Royal Ruby’’ and was produced for Schlitz by Anchor Hocking Glass from 1949 to 1950 and again in 1963. Bottle collectors claim some ‘’Royal Ruby’’ bottles were also used by breweries producing the Old Milwaukee and National (Baltimore) brands beer.
Within the family of blue colors, turquoise is considered the most rare. Turquoise was a color seldom used in the mass production of bottles, so it obviously stands out as one of the most difficult sea-glass colors to find and can be assumed to be older than most pieces. This intense blue color with a samll degree of green was sometimes used in tableware, antique flasks, and art glass. By adding small amounts of copper or iron compounds to raw glass mixtures containing cobalt, glassmakers could generate turquoise blue. But turquoise was a problematic color to keep consistent since cobalt is such a strong colorant. It has been noted that ancient glassmakers used copper and tin to create turquoise glass, wich also happened to be key ingredients in bronze production. In recent years, copper has been used more frequently to created turquoise.
Yellow sea glass may not be as desirable as red, but there were few mass-produced yellow bottles, making is almost as rare. Yellow glass has been used primarily for tableware and ornemental pieces, and these were less frequently discarded near the shore. Some pale yellows were made in transparent Depression glass tableware, and a very limited amount of opaque yellow was produced, sometimes using fused layers known as ‘’flashed glass’’.
Since spirits and medicines frequently needed protection from sunlight, early glass manufacturers often produced dark, almost black, glass. During the 1700s, numerous Dutch ‘’onion-shaped’’ black flasks containing gin were imported into the United States. In most cases, the glass was actually an exceedingly dark green but at times was dark amber. By shinning a bright light behind the glass, one can see the true color one hiding behind what appears to be black. Producers added iron slag to the glass batch to create the dark green color, but this ingredient also provided an additional benefit in that it made the vessels resistant to breakage. As a result, shards in this color are routinely found as large, chunky pieces rather than petite and rounded.
Teal is an other member of the blue color family that is far more than cobalt blue. There was not a wide variety of items made in this unique blue-green color. Whit a small amount of cobalt and iron, the teal color could be created, but holding it consistently between batches provided a challenge similar to that for turquoise, contributing to its rarity. Chromium was sometimes added to boost the green color, and in more recent years, aluminium oxide has been used with cobalt to produce a teal color.
Gray-colored glass is especially atypical, as it was often an undesirable by-product resulting from what was originally intended to be clear glass. Manganese was commonly used to remove the green or blue color created naturally from iron impurities in the sand, but if both copper and iron were present, the collective elements could slowly develop a gray tint. If certain element within the glass were oxidized by extended exposure to sunlight, the ‘’color mixing’’ of purple, green, and light blue (from manganese, iron, and copper) could create differing shades of gray, which could resemble smoke-colored glass with slight blue-gray or green-gray tints. It is also possible that pieces of antique lead crystal can develop a gray cast. In more recent times, nickel was used to produce smoky gray-colored glass.
Pink glass is an other rare color that was primarily produced as tableware during the Depression era. Selenium was added to produce pink-colored glass and even shades of red. But it is much more likely that the sea-glass collector might find shards of ‘’sun-colored’’ pink from pieces that were originally clear. ‘’Sun-colored’’ glass refers to the process of altering the atomic structure of glass colorants through interactions with ultraviolet radiation.
Unlike the deep blue hue created by adding cobalt, copper is used to create a rich aqua color. Aqua-colored glass, especially deep aqua, is less common than the cobalt-blue color. Before the turn of the century, a generous amount of aqua glass was used for soda, mineral water, and even beer bottles before later becoming a popular color for fruit jars, such as the Ball Mason jar. Another later form of aqua glass, wich is easily recognizable, is the mass-produced telephone pole insulator. In general, the thicker the piece of glass and the deeper the aqua color, the more likely the shard is from an antique bottle or an insulator. For example, the upper shoulder or collar of a fruit jar may show a more concentrated form of the aqua color than a piece from its midsection.
The colors of cobalt blue and cornflower blue are two of the most popular colors with glass bottle, decorative arts, and sea-glass collectors. Adding cobalt oxide to a molten glass mix creates these colors. This colorant is one of the most forgiving to work with in creating glass objects, since heating times and specific temperature do little to change the color once it added. That is because cobalt oxide itself has an extremely high melting point, well beyond what is needed to melt the silica batch. Thus it was much easier to produce identical blue colors from batch to batch.
To created the color of cornflower blue, such as that used for early Milk of Magnesia bottles, the manufacturer simply limited the dose to a fractional amount of cobalt additive. Since there was much less cornflowers-blue glass produced, sea glass in that lighter tone is significantly more difficult to find than in regular cobalt blue. Dark cobalt blue was used frequently for poison bottles and general medecine bottles to clearly distinguish them from other bottles. Iron in the sand helped deepen the blue color created by the cobalt colorant. The shapes of poison bottles were even modified in the early 1870s to be unique to the touch. That way patients would not grab the wrong bottle in the dark, resulting in a tragic mistake.
Opaque white glass, commonly referred to as ‘’Milk glass’’, has been produced worldwide for hundreds of years. The Venetians are recognized as its originators during the 1500s. In the United States, Milk glass was quite popular during the late 1800s and up until the 1950s. To create its opaque white color, tin or zinc compounds were added as the primary colorants. Other opaque color also referred to as being ‘’Milk glass’’ include green, blue, and purple. There was also a limited amount of a nearly translucent off-white glass produced named ‘’clambroth’’ because of its virtual skim-milk appearance.
The yellow-green color termed ‘’citron’’ is also one that falls in the rare category for sea-glass collectors. Since this was often a color used to bottle wine, it can be found more frequently in some areas than others. There were a number of fruit jars, snuff jars, and various other bottle made in the color citron, butthey are less far common, and they often command high prices in the bottle-collecting market.
Early glassmakers dating as far back as 2.500 B.C. found that manganese oxide could be added to glass to mask the aqua or green color that normally resulted from iron and other impurities in the sand. When too much manganese was accidentally combined in the batch, soft purple colors could develop instead of the intended clear glass. Later it was purposely added in excess to give the glass a deep amethyst color. Some glass producers, such as The Boston and Sandwich Glass Company in Massachusetts, claim to have used raw amethyst quartz in the 1800s to produce deep purple colors. However, manganese was clearly less expensive.
The experienced collectors can easily identify the soft green color from a piece of the ribbed Coca-Cola bottle. This bottle began its reign in 1915 and saw a good 60 year run on the market. Sea glass hunting near beach resorts that flourished in the early to mid 1900s should reveal a fair number of these shards. The color of the Coca-Cola bottle actually fluctuated a bit from a soft green to a soft blue-green, and then to almost a light aqua color during its reign. (Coca-Cola bottles were initially made in clear glass.) Iron was the primary ingredient for creating the soft green color. However, if copper was present, a mild amount of blue could sneak into the bottle color. Coca-Cola bottles were produced all over the world, so slight color variations could be expected.
Late 19th and early 20th century items – soda bottles, fruit jars, patent medicine, and ink bottles – are common sources for soft blue sea glass. One may note that the soft pastel blue pieces from bottle shards often contain bubbles within the glass. This is indicative of bottles made before automated machinery virtually eliminated the bubbling defects (called seeds) in the early 1900s. Windows and windshields are also frequent sources of soft blue glass shards. These can be easily identified by their flat surface and uniform thickness.
The color of »forest » green is not quite as rare as the earlier noted »black glass » but ranks higher than most other greens as far as rarity. This darker green tone could be from shards made prior to 1900, but since the color is still used today for wine bottles, dating it only by color is not practical. There are several color tones that can be included in the forest green area. In most cases, the bottle color was chosen to protect its contents from sunlight. Forest green can be achieved by using a generous amount of iron oxide and possibly a little oxidized chromium. At times, some copper was added to create a slightly bluish tone. The forest-green color was popular with a wide variety of antique spirits bottles including case gin, beer, wine, occasional snuff bottles, some bitters bottles, and also flasks. Since the color has been used considerably over the past century, opportunities of finding forest-green colors are about one for every 50 pieces picked up.
Unlike most of the rare colored shards of sea glass noted earlier, the »lime-green » color is normally found in bottle glass made in the mid to late 1900s. Given that it is a more recently manufactured color, note that most of he pieces found are small in size and rarely as smooth and rounded as other colored shards. This is due to the fact that most modern vessels are frequently made with thinner walls that tend to shatter into petite shards. Large, well rounded shards of lime-green color can be considered a bit more rare since they may be from 32 once soda bottles produced during the 1960s and 1970s. The smaller pieces are not quite as rare but are definitely harder to find than the more common »Kelly » green.
The most rare hue in the family of brown colors is the soft yellow tone of brown sometimes referred to as golden amber or »mustard » color. It can be surprisingly attractive when wet, as it shows a rich yellow-gold hue. This color was used for spirit bottles, some patent medicine bottles, a few bitters bottles, and a variety of small bottles. Larger brown bottles were usually made in darker brown colors due to the greater durability lent by increased amounts of iron oxide. the golden amber color can be produced with cerium colorant and iron. Some claim it can also be produced with oxide manganese and iron. Often the color will appear very close to yellow as the glass becomes worn and thin.
Dark reddish-brown bottles were commonly used for holding whiskey, bitters, snuff, and even a few poisons in the late 19th century. This dense amber color provided strong ultraviolet protection for some spirits, medicines, and even chemicals. Some well worn pieces early Clorox bottles can show this tone of red amber, but when the sea-glass collector finds an antique shard of brown, it may require a quick dip in the water to tell if it is a true amber or standard brown.
A deep jade-green color is actually a favorite for many collectors of sea glass because of its similarity to emerald gemstones. Since it is a color that has been made throughout both the 19th and 20th centuries, dating pieces can be a formidable challenge. The color actually has a much richer hue than the common Kelly green color. Finding thick pieces of jade colored glass is more probable than finding thick pieces of Kelly green or lime green shards, as those are more recent productions and usually of thinner construction. Not many bottle designs were produced predominantly in jade green, but several flasks, soda bottles, bitters, mineral water bottles, and even some poison bottles did come in this color.
Medium or »Kelly » green falls into the category of common colors since it has been a mass produced color for bottles during the second half of the 20th century. This green shade has been popular with various contemporary beer and soda manufacturers such as Heineken, Molson, 7UP, Sprite, Montain Dew, Schwepps and Canada Dry. Prior to the 1950s, this medium hue of green was used far less, so most pieces can be dated as produced in the late 1900s. Copper and iron have been common colorants for green, but chromium containing compounds mixed with arsenic or tin will also create a vivid emerald green color. The variable thickness of the shard will make the color range fro a rich green to pale almost pastel green.
Dark brown colored bottles were popular in the late 1800s, especially for whiskey and bitters, but remain in particularity frequent use today for American beer, liquor, and wine bottles. The brown color protected the bottle contents from sunlight and was more compatible with large production demands than some others colors. Clorox bottle were made in dark brown since sunlight rapidly diminishes the strength of Chlorine. A great site for dating those shards can be found at »The Clorox Bottle Guide ».
What begins as clear glass is slowly pecked away by abrasive and corrosive environments to produce a practically snow-white piece of »frosted » sea glass. When wet, its transparency nearly returns, but as it quickly dries, a well-worn piece becomes almost opaque again. To make clear glass, black oxide of manganese was the preferred ingredient to add during the first several centuries of glass making. It was even used to help clarify high-quality leaded glass in 1674, when George Ravenscroft developed the first formula for leaded glass in England.