BOXWORK

in geology, honeycomb pattern of limonite (a mixture of hydrous iron oxide minerals) that remains in the cavity left when a sulfide mineral grain has dissolved. The boxwork may be spongelike, triangular, pyramidal, diamondlike, or irregular in shape and may be coloured various shades of ochre and orange through dark brown. The colour and shape of the boxwork are often used to identify the dissolved sulfide minerals. See gossan.