The dark red zones are the high grade spodumenes zones. The light red zones are the minor to moderate spodumene zones. If you do not know what this means it is in relation to the grades. It is normal for the grades to differentiate in parts of the pegmatites.
Companies will report the average grade like this
50m @ 1% Li2O
including 30m @ 1.5% Li20
The assays will tell the true story
