Like KRB10, plagioclase and clinopyroxene are intergrown in an almost graphic texture, though where KRB10 was dominated by the unknown mineral, in KRB11, that unknown mineral is confined to spherulite-like clusters in a fine-grained quartz matrix. Iddingsite alteration is much less extensive. Western Minerals Inc. as an 'interstitial ferrotholeiite, very highly fractionated…textures are similar to those associated with rapidly frozen or highly viscous melts.'
The groundmass in this thin section is a salt-n-pepper mixture of fine-grained, amorphous quartzofeldspathic phases. All phenocryts are subhedral in shape, and the largest of these, the k-feldspar and plagioclase are host to abundant hematite-filled fractures. Biotite and hornblende phenocrysts are much smaller. A few spherulites, seen more clearly in plane than cross polarized light, are found in the groundmass.
