This quarry is still in operation, and has cut through some old Cu-mines (Alnsjø mining field; Aanerud Mine and Nedre Grorud Mine). The dominant rock is basalt which is cut by several different veins of rocks like "Grorudite" (peralkaline microgranite), quartz-porphyry, diabase, syenite, andesite and a vein of anatase and albite.
Refs.:
- Berg, H.-J. (1990): Etter Neumann. Scheelitt. CaWo4. Montmorillonitt (Na,Ca)0,3(Al,Mg)2Si4O10(OH)2 * nH2O. STEIN 17(3), 40.
- Kvamsdal, L. O. (1999): Mineralene fra Huken pukkverk i Oslo. STEIN 26 (4), 14-47.