If all one finds at the burial site of some planetary civilization - much like ours, is one small piece of banded agate orbiting the charred Sun, what would it say?
The colorful layers and meandering strata would indicate many thermodynamic cycles of hot and cold that breathed against the rock, while it metamorphosed into its crystalline form.
If the specie reading the stone has a finer grasp of gravitational dynamics than us, it may be able to detect the push and pull of periodic tides exerted from the orbital resonances between different planets and a belt of asteroids over millenia. Perhaps it may even record the births and deaths of new planetoids, or the visitations of comets. The differential geometry of its curves might encode an imprint of eclipses, occultations and syzygys.
The subtle variations in the widths of outer layers might indicate the rising global temperature due to some new form of carbon-based emission. A magnetic signature of the changing fields, their gradual intensification due to some new sentient source of electricity gradually overtaking the planet like slime mould or lightning slowed down to a crawl.
The exposed surface of the stone would carry the bruises from its trajectory in space through lesser debris or solar wind, and a faint signature of the explosive ejection from its incubator.
Perhaps the most remarkable testimony of the stone would be the perfection of its circles. How could a merely diffusive chemical reaction produce circles which rival the precision of a human compass? Or are these concentric circles the etched memory of every single diurnal rotation of the planet on its solitary axis?
In the words of Roger Caillois: “They provide moreover, taken on the spot and at a certain instant of its development, an irreversible cut made into the fabric of the universe. Like fossil imprints, this mark, this trace, is not only an effigy, but the thing itself stabilized by a miracle, which attests to itself and to the hidden laws of our shared formation where the whole of nature was borne along.”
- The Writing of Stones, Marina Warner: Cabinet magazine article about Roger Caillois
- Photographs from Roger Caillois (1970)
- Banded Agates, Sonic Hydrodynamics & the BZ Reaction, by Paul Prudence
- Maori Stones Hold Magnetic Clues, BBC