Table 7: Quantitative analysis indicating the amount of each mineral present and the extent of alteration
Scores
1 2 3 4 5 6 7 8 9 10
Colour (of thin-section to naked eye)
Transparent, colourless Near opaque, very dark greenPredominant non-green colour
Grain size (from estimates of original pyroxene average grain size)
<0.25mm 0.25mm 0.375mm 0.50mm 0.75mm 1.00mm 1.50mm 2.00mm 4.00mm >4.00mm
Pyroxene alteration (visible in thin-section through x4 and x10 magnification)
All pyroxene grains are unaltered (i.e. fresh) Less than 50% of pyroxene grains have <5% altered A majority of the pyroxene grains have <10% altered All pyroxene grains have <25% altered All pyroxene grains have between 25%-75% altered All pyroxene grains have between 75%-95% altered Less than 5% unaltered pyroxene Small amounts (<5%) of unaltered pyroxene Possible pyroxene pseudomorphs No evidence of pyroxene
Feldspar alteration (visible in thin-section through x4 and x10 magnification)
Fresh, unaltered Fsp with clear cleavage and twinning Less than 5% alteration on 50% Fsp; clear twinning evident, cleavage not apparent All Fsp <10% altered: clear twinning evident, cleavage not seen All Fsp between 10% to 50% altered: clear twinning evident, cleavage not seen All Fsp between 50% to 90% altered: clear twinning evident, cleavage not seen Less than 10% original Fsp: twinning evident, cleavage not seen All Fsp altered, with clear ghost shape and twinning obvious All Fsp altered, with ghost shapes and suggested twinning throughout All Fsp altered, with ghost shapes and suggested twinning evident in few places No evidence of Fsp
Opaque minerals (seen in thin-section through x4 and x10 magnification)
Coarse, angular opaque grains, >2mm Coarse opaque grains, with alteration and skeletal structure or elongate grains >2mm Coarse angular opaque grains with clear polygonal skeletons >2mm Medium, angular opaque grains, 0.5mm to 2mm, with no skeletal or ladder-like lattice seen Medium angular opaque grains, with distinctive polygonal skeleton(s) 0.5mm to 2mm Medium angular opaque grains, with elongate/ladder-like grains 0.5mm to 2mm Medium angular opaque grains with eroded appearance and no skeleton visible 0.5 to 2mm Fine opaque grains <0.5mm Opaque grains different from descriptions 1-8 No opaque grains seen
Amphibole and Mica (chlorite and biotite)
No amphibole or mica seen Primary amphibole present Secondary amphibole present 
Epidote
No epidote present Very fine cloudy masses present Distinct, small (<0.2mm) grains present 
Apatite
No apatite seen Small grains (<0.1mm) present Larger grains (>0.1mm) present or plentiful fine-grained apatite 
1 2 3 4 5 6 7 8 9 10