Hard to tell from the pics. How thick are they? They look like dust pressed tiles to me.
A portland cement tile that is kiln dried rather than fired. It has 2 layers. Portland cement on the top and portland/sand for the base.
They dont usually have any glaze to them and as you say are seriously porous.
Most customers want them shiny which can be a nightmare due to their porosity. I always try and swing them in the direction of colour enhancing impregnator.
They take over a week to dry out. Especially this time of year so it will mean a couple of trips.