What materials suffice for the Rami (stoning)?
Chapter on the Description of Hajj
Al-Mughni
Book of Hajj
Primary text
It suffices to use anything termed 'hasah' (small pebbles/stones), regardless of color (black, white, or red), or material, including marble (maramar), barm, flint (marw/sawwan), limestone (rukham), kadhan, or a whetstone (hajar al-musann). This is the position of Malik and Shafi'i. The evidence rests on the Prophet, peace be upon him, throwing pebbles and commanding throwing pebbles like 'khadhaf' pebbles, which encompasses all its types, prohibiting arbitrary specialization or analogical addition where analogy is inapplicable.
Supporting text
Al-Qadi stated that limestone (rukham), barm, and kadhan are not sufficient, implying that flint (marw) and whetstone (hajar al-musann) are also insufficient. Abu Hanifa and Thawri permit the use of clay and hardened earth (mudr) or anything originating from the earth.