Glass Cleaning Tips

I clean a lot of glass in my work, and whether it’s my blown glass that I’m getting spotless for a show, event, or customer, or whether it’s getting the shelves on which the work is to be displayed, getting glass clean has become both science and art. I thought I’d pass along a few tips for cleaning glass that I have found indispensable. 
First, forget glass cleaners. That’s right, forget them. I’m sorry to say that while the rest of the world is using Windex glass cleaner, I have long since given up on this product for a far superior product that is more effective and, gasp! Cheaper!
Glass cleaners do clean glass. The problem with cleaners like Windex is that they contain polish and this always leaves a film behind. If you want a cleaner that gets right to it and leaves no residue, buy a gallon of distilled white vinegar. It cuts grease and dirt and leaves no residue once all dirt and grease are dissolved. The nice thing is that vinegar is an excellent degreaser and I have been using it exclusively as a cleaner for my glass as well as my kitchen counter tops and surfaces. The advantage here is that there are no more chemicals or dyes and the cleaner is as hypoallergenic as you can get. 
Remember to get distilled white vinegar since this has no residue from the fruits used to make it (like Apple cider vinegar has).

A Magic Material

Next on the list is not even a cleaner per se, but a material that cuts down significantly on your use of vinegar in the first place. This wonder is called a microfiber cloth
Microfiber came into vogue over a decade ago, and once I was given one by an exhibitor with whom I shared some technical information with (as a kind thank-you), I became a believer in its ability to spit-shine my glass…..without the spit!  If you haven’t used microfiber yet, you should, because it can greatly reduce the need to use ANY cleaning fluids on mildly mussed glass. 
The fibers pick up dirt extremely well and lock the dirt in the fibers. Just remember to give your cloths a good cleaning with mild soap and a vinegar rinse every so often. It is good for dozens of cleanings of window panes, metal objects, or just about anything shiny (do be careful with plastics, love, as they can be mildly abrasive to them). Just bear in mind, microfiber will work only on dirt films on glass and is not designed to sop up big spills. For that, I offer the towel, be it paper or terry cloth.
If you bring these two simple ingredients into your arsenal of cleaning, you will find your world cleaner without the need of the expense of the vast cornucopia of chemistry now under your kitchen sink. 
I hope that you have had a marvelous holiday, and if things are in need of a little cleaning, I hope you will give my suggestions a try. My work here is done. Godspeed and good morrow, my dear glass enthusiasts!

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The Mystery Of Libya’s Desert Glass

I was on my last few hours of my open studio event recently, when in walks a woman who begins to tell me a story about how her father had gotten funding to study the presence of a naturally occurring form of glass in the desert of Libya in the ’50’s.

I was hooked because….well….chemistry, that’s why. And….glass of course!

You see, naturally occurring glass is rare because most often the glass is close to being pure silica simply because sand beds where the glass is formed is made up of almost exclusively silica. When you make a glass so pure as 90%+ a silica, it takes extraordinary temperatures to get the silica to go into a glass phase. It is why we humans have added things to silica to coax it down from the high temperatures required to melt it. Simply put, we use fluxes to achieve a lower melt temperature  

But the temperatures! My God! 
To melt pure silica you need temperatures in excess of 3100° Fahrenheit. It’s hotter than even the best constructed open air fire could hope to reach on earth. 
Without going into great detail, the types of magmas found coming up out of the earth have temperature ranges that depend on their mineral content. High silica magma, like the glass found in Libya, is recorded with a high mean temperature of 1472° Farenenheit. This is called Felsic magma and it’s lower temperatures are due to how magma, we believe, is formed in the earth, which is that iron is melted first, and then flows up through cracks and fissures in the earth into what we know to be volcanos and volcanic vents. As a result of this, sand, which we think lies at layers higher up, only tends to get a lesser heating effect so that it’s average temperature is lower than iron rich magma, whose temperatures are much higher.
Comparing the melting point of silica and it’s average melt temperature through natural means yields us a very broad temperature disparity. What gives? How on earth could this glass have been formed here so close to the surface of the earth where so much of this material has been found?
First, you should know that glass (or silica) does not have a discreet melting temperature. Instead, it has what we call a melting range. It’s not unlike how honey will change viscosity from thick to thin all depending on the temperature that is affecting it. So while silica forms a perfect union all on its own of a glass we call quartz glass (nearly pure silica) at 3100° F. it begins to go into a glass phase at lower temperatures. At 14-1500° F. silica is glass-like, but it’s also very much sand-like, too.  You would look at it and tell that its a very crude form of glass (very unlike the glass found in Libya).
The question on everyone’s mind has been, how did this Libyan desert glass form to begin with?
The Comet Theory
First, there are a lot of theories. One theory is that the silica was heated in our atmosphere as a result of a comet that fell to earth millions of years ago. This, the theory goes, was what created the extraordinary heat necessary to melt the silica.
But there are problems with this theory. A body falling to earth only takes a few minutes to go from our upper atmosphere to the surface of the earth, which may not be nearly enough time to heat up a comet and fuse the quartz into the glass that has been discovered on the desert floor. To make glass like what my visitorsfather studied in the ’50’s, you need enough time to really get the melt right. A meteor can enter our upper atmosphere and fall to earth within 15 minutes time (or less). Hardly enough time to get the silica cooking deep down in a comet.
The Volcano Theory

Another theory is that the silica was heated by volcanic means. Normally, however, we wind up seeing either basalt glasses, or very crude lower temperature glasses of the kind I described earlier. The Libyan glass is different from both of these kinds of volcanic glasses.
So as a result, researchers who have been studying this for a while now have looked at the region and have offered a new theory.

The Sol-gel Theory
When researchers began to study the geology of this area they found evidence of ancient volcanic activity. in fact in what they considered to be the bullseye of where most of the glass is found they also found a corresponding evidence of ancient volcanic activity in exactly the same area. Normally volcanic activity is not enough to melt silica into the type of glass that we find in the Libyan Desert glass.
There is a process however where silica can be heated over and over many times in order to create glass from silica. Researchers posit that the glass was made through a process called sol-gel which consists of small silica particles that melt and then slowly form glass, a process that could take many years of repeated heating and cooling in order to form a solid glass. One example of a sol-gel that you might be familiar with are opals, which are silica based particles along with other minerals that are repeatedly heated in volcanic vents that form the gems with rainbow colors that we know so well. The reason why the Libyan glass does not look like opals is because the conditions and the substance of the silica beds were very different than the ones in Australia that produce opals (which is a sol-gel process).
This theory offers the most likely possibility for how the Libyan glass was formed. While we can never be completely sure, it seems that in this one place on earth conditions were right many millions of years ago for this unique form of glass to be created.
I’m very thankful to have had such an interesting conversation with Robin who first told me about her father’s work because it put me on the path of a great mystery that lies in the sands of the Libyan desert. And of course, since it’s about glass, it naturally piqued my interest!
Source: http://nationalgeographic.org/encyclopedia/magma/