This is an extremely rare form of Echeveria purpusorum which has white colouration with red outlines. These are so highly collectable as they are extremely hard to come by. It is a strong structural plant with robust leaves and form, a truly choice plant.
It is a slow grower and to keep the white colouration it will need to be grown hard with a bright light.
This plant will lose its white colouring in a higher nutrient compost mix, so to keep the strong white colour you can plant it in a 50/50 gritty succulent mix.