Antimony Trioxide -A common fining agent for chemically durable glass

Antimony Trioxide -A common fining agent for chemically durable glass

By adding sodium bicarbonate, calcium oxide, magnesium oxide, and aluminum oxide to silica, you can make very chemically durable glass. However the glass isn't perfect yet. Tiny pockets of air tend to get caught in the melt while it's being mixed and poured. The resulting bubbles can cause performance and aesthetic issues in the final product.

You need to add a fining agent to the mixture to get rid of the bubbles. An example of a common fining agent is antimony trioxide. The antimony oxide causes smaller bubbles to come together and form larger bubbles. The smaller bubbles raise to the surface of the melt very slowly while larger bubbles travel relatively quick. With the addition of a fining agent and a bit of patience, glass will be bubble free.

Glass Blowing

Glass blowing is a form of art which has existed for many centuries. Before the 1900s glass blowing was more of a practical glassware production technique rather than a dedicated art form. There weren't any technological alternatives to making glassware other than hand blowing. In fact, many of the early chemists were proficient glass blowers because they hand to make their own custom glass to carry out their chemistry experiments. During the later part of the industrial revolution manufactures began to automate the production of glass products. It was at this point in history that glass blowing really emerged as an art form. However, interest waned in the new art form beginning in the early 1930s. It wasn't until the 1960s, when glass blowing enjoyed a tremendous revival.

Today there are many artisans creating quality blown glass works of art in many different forms. Pieces range from glass vases and faucets to more decorative works of art. A great example of decorative art work is Dale Chihuly's Fiori di Como. Fiori di Como is a very large series of flowers that hangs from the ceiling of the Bellagio Hotel and Casino in Las Vegas, Nevada. Fortunately, you don't have to commission an artist to create blown glass artwork to be able to enjoy the beauty of hand blown glass in your home. Companies like Blenko Glass Company produce early collections of beautiful vases, decanters, bowls, bookends, pitchers, candle holders, and ornaments. You can also purchase tumblers and carafes as well. Most of these pieces of art can be procured for less than $200.

What is Glass

Technically, glass is any inorganic substance that has been heated passed its melting point and then cooled into a rigid object without crystallization.  Really any amorphous solid is considered to be a glass.  Amorphous solids cover a wide range of materials including organics like plastics, biological compounds, and resins.  I'll be talking mostly (exclusively) about inorganic glasses.  For example, volcanic glass is an inorganic glass.  The first volcanic glass that comes to mind is obsidian, but pumice is also a volcanic glass because it lacks a crystal structure.  However, inorganic glass also covers a lot of territory, so I plan to focus on glass made from silicon dioxide.