Figs Jands. diabaserporphyrite from Miohrpsecten Tsland 
ordinary crpht. Fig.2 seate t/ diameters. polarized Zepht. 
Fig. 7 Seale 7 @zamcters, 
Jee pages. rt, 78 Fb, 244, 
Parphy rite labradorite tiara augzte(2/, reth the latter is assoceated mmagnelete(s/ and & 
Greenrsh akleratconpro duct (¥/ / 7e@ Starne@ insoluble groundmas($/, Carrying enru- 
merable mioroliths of plagroclase 
Lhe latter are. very rnadeguatety Shomuzn the 
engraring, their representatcon dering. Beyond the engravers art. 
Fey S ‘drahaseporphyrile Jrou Duluth, Meni. 
Scale vg deameters,  Ordcnary leght Jee pages XU PZ TT 
Porphy rete urthoclare(1/ and olrgocdase(2/ often mth an 
eprd@otec alteration(s/; bace (4) Conse sle? lageocdare, 
magnets te, auge €e, pre wudamyg dalovd 
ancl 
an trresolrasle rudvtance 
Ys». 
l, 
= 
Hg. 4 ashbed-diabase from Lotoyatrg Rrver, Mek. 
Scaletodrameery Lelarized Ceght See pages ati, P9 
Plagroclareyjaugrte in prarns(2/; magnretile (7. 
