Bl This standard refers to resins of the type called copals, which are commonly used in the preparation of varnishes. Three types are standardized: a) Congo copal b) Kauri copal c) Manila copal. C - DEFINITIONS Cl Copales. It is a group of resinous substances, of fossil or recent origin, coming from different botanical species, generally from tropical areas. C-2 Copal congo. It is copal characterized by its extreme hardness and insolubility. C-3 Copal kauri. It is hard copal, with general characteristics similar to the con-go type and partially soluble in alcohols and ketones. C-4 Copal manila. It is copal characterized by its solubility in alcohols and ketones.