stripes
Numerous dykes and sills of micaperidotite and lamprophyre and bodies of intrusive breccia are found across the Hicks Dome. Intrusive breccias in one body (Grants Intrusive) contain fragments of aegirine-bearing syenite (Grogan and Bradbury, 1968, p. 375). The matrix of this rock is dolomite, but whether it is of secondary or primary origin is not clear. A nepheline-feldspar rock has also been found (op. cit., p. 376) which contains an amphibole and aegirine-augite.
GROGAN, R.M. and BRADBURY, J.C. 1968. Fluorite-zinc-lead deposits of the Illinois-Kentucky mining district. In Ore deposits of the United States, 1933-1967. J.D.Ridge (ed). The American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc., New York: 370-99.
ZARTMAN, R.E., BROCK, M.R., HEYL, A.V. and THOMAS, H.H. 1967. K-Ar and Rb-Sr ages of some alkalic intrusive rocks from central and eastern United States. American Journal of Science, 265: 848-70