Refractory, CRM, set of 10 x 20 g (1 x 20 g each of JRRM-301, JRRM-302, JRRM-303, JRRM-304, JRRM-305, JRRM-306, JRRM-307, JRRM-308, JRRM-309 and JRRM-310), Powder