Methodical path algebraic /
Yields greatness from parts formulaic /
With images’ building /
From artisans’ gilding: /
In tesserae, steps toward mosaics.
This week’s summer poem again describes a more random theme. This one commemorates a combinatorial art form that I had been intrigued to learn more about, in developing some of my general education courses over the past academic year.
“Methodical path algebraic / Yields greatness from parts formulaic…”
The fresco is generally my go-to source for chem-artistic themes, but I also have enjoyed learning more this year about the use of mosaics throughout history. I had been aware of mosaics as compilations of tiled pieces for a while (thus thinking of them as a “methodical” process with “parts formulaic”), but I learned much more about the underlying materials in preparing my spring courses.
“With images’ building / From artisans’ gilding…”
For one point, the tiled mosaic pieces themselves are known more precisely as tesserae, stemming ultimately from the Greek word for “four,” commemorating the geometric nature of the piece and anticipating terms like “tesseract.”
For another, the use of gold foil in building some tesserae has been new to me, and it is quite fascinating. Gold foil would be sandwiched between pieces of glass, then used to build up larger areas of gold on mosaics. I have encountered discussions of how such tesserae were designed for religious environments, where candlelight’s reflection off a mosaic surface could be particularly striking. While candles are no longer common lighting sources, the reflective effects endure.
This makes sense: gold would famously NOT undergo the same redox chemistry that can change many artworks’ appearances over time. (Gold is sometimes called a “noble metal,” given how little reactivity it exhibits, in a designation parallel to that of the noble gases.)
“In tesserae, steps toward mosaics.”
I will record two connections here that I’ve noticed briefly in teaching and hope to write about more formally here, during the upcoming academic year.
First, it is fascinating to compare and contrast a tessera, as an intentionally uniform and standardized piece of a mosaic, with the comparably constituent part of a fresco, denoted the giornata (for “a day’s work”) and thus highly individualized, since it was set out each day by the artist themselves.
Second, gold’s malleability, specifically, is a property that (appropriately!) casts a wide and interesting shadow. Malleability is the ability of a metal to form a sheet; this ability allows gold foil’s use in mosaic art; it is famously cited as an aspect of the metal’s elemental properties; and it played a huge role in Rutherford’s key “gold foil” experiment, which provided experimental evidence ultimately supporting the nuclear model of the atom.
Chemphasis 