Bacaad-qarxinta waa habka oo dhan ee ka saarista iyo dhex-mareenka dusha sare ee substrate iyadoo la isticmaalayo socodka ciidda degdega ah. Gaaska la tuujiyey waxaa loo isticmaalaa sida xooga wadista si loo sameeyo buufin xawaare sare leh si ay si dhakhso ah u buufiso walxaha buufinta (ciid oreed, ciid quartz, ciid bir dahab ah, ciid bir ah, Hainan Prov ...
Akhri wax dheeraad ah