El Defecto Del Mes

June, 2023
Weather Radar Map
This image bears a striking resemblance to a weather radar map. In reality it is an EDX spectral map conveys a huge amount of information by portraying each element in a particular color. The different areas are portions of a stone found in a glass container that have partially melted or recrystallized. This particular stone resulted in glassy areas (blue and yellow) that separated into calcium-rich and calcium-depleted phases. The red area is composed primarily of zirconia (ZrO2) and the green area is composed of alumina (Al2O3) with magnesia (MgO). The magnesium and zirconia are not found in the bulk glass composition, indicating that the stone likely originated from a refractory source.
January, 2023
Drop of Gold
Glass can be produced in a kaleidoscope of colors through the inclusion of small amounts of metal oxides in the glass composition. In the art glass industry, where color is paramount, exotic metals or metal oxides can be used that would be cost-prohibitive for food or beverage containers. Since the late Roman empire, gold has been known to create vivid red hues when added to glass. Although the host glass in this microscopic image is not red-colored, this particular stone is composed of excess gold that lingered in an art glass furnace from a prior batch.
December, 2022
Holiday Gemstone
The sparkly silver sphere in the center of this microscope image is the fractured surface of a silicon ball, a type of stone. Silicon balls are created when aluminum contamination of the cullet supply reacts with the molten glass, causing a chemical reaction that reduces the silica (SiO2) to silicon (Si). The red color of the glass is due to a painted decorative coating on the host bottle. Silicon balls are especially detrimental to container performance because they create extremely high induced stresses in the surrounding glass, often leading to spontaneous breakage of the item.
November, 2022
Snowball Fight
Bottle formation takes place in an Individual Section (I.S.) machine, which has with many moving parts. Mechanical equipment requires lubrication, including mold dopes, grease, and oil. When one of these lubricants comes into contact with hot glass, it pyrolyzes and burns down into a black carbon crust. In this microscope image, a crust of pyrolyzed lubricant from the inside bottom of a bottle is shown, indicating that excess lubricant was introduced into this hot bottle during formation. Since pyrolyzing destroys the original molecular bonds of the material, the use of FT-IR or other chemically sensitive analysis techniques were prevented and specific lubricant components could not be identified.
October, 2022
Shelob’s Lair
In the Lord of the Rings movie, Frodo is led by the treacherous Gollum into the lair of a giant spider. Fleeing in terror, he is entangled in the massive webs and narrowly avoids being eaten alive. Although on a much smaller scale, this SEM micrograph of a flaw in a cosmetics container resembles the lair of an arachnid. The unusual flaw likely resulted from a fold in the glass being pulled apart during container formation, causing strands of glass to stretch across the fissure. Based on its appearance, the flaw would likely be classified as a tear or an infolded lap mark.