What are convection currents in Earth's magma?

Convection currents create the movement of Earth's tectonic plates in the magma.

Explanation:

Heat from the core and the mantle itself causes convection currents in the mantle. This flow, called mantle (magma) convection, is an important method of heat transport within the Earth. Mantle (magma) convection is the driving mechanism for plate tectonics

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

practical process described pest part of scientific investigation.

because practical knowledge is powerful then therotical knowledge.