This looks like it could be a fabric print, but in fact you’re looking at magnified view of a phenomenon known as Rayleigh-Benard convection, as temperature differences drive the motion of silicone oil.
Convection occurs when temperatures differences create subtle differences in density in fluids: less dense liquid rises but cools as it does so, and then sinks again. In this image, small cells of fluid see the liquid rise through the centre of a hexagonal unit, then sink along its edges.
The distinctive pattern is a result of the surface tensions of the liquid: here, it’s open so held at atmospheric pressure, but different situation would give rise to different patterns. Incidentally, you can see all this happen because there are tiny aluminium flakes in the oil. Otherwise it would almost impossible to see what was happening. [Fuck Yeah Fluid Dynamics]
Image credit by M. Velarde et al