Amphibolite is a combination of amphibole and feldspar. These minerals are types of aluminosilicates (similar to spodumene), so while they are a good indication of all the makings of a spod rich pegmatite, you still can't really tell anything about the actual level of lithium fertility with the information on Sigeom.
The only guess you can make is if nearby pegmatites are rich in lithium, try and connect the dots to a common source/parental granite. If you believe Cosmos's pegs share the same granite as Corvette (which personally I do), it would be fairly reasonable to assume at least a similar Li mineralisation since they come from the same originial melt.
So if you have the same parental granite/fluids, the last thing left is to infer a level of fractional crystallisation, which is basically just the level of Lithium crystallising from the granite melt in the pegmatite. This increases with distance to the source granite, so I would love to see the level of Li mineralisation at 'Corvette East' since it is at a similar distance to the granite as Cosmos (shown in black).
My guess is that we will have similar Lithium content to the 'Corvette East' area in our pegmatites, if exploration comes up positive. This is just a somewhat educated guess so take with many grains of salt lol.
So yes the compositions of these pegs are what you would expect of LCT pegmatite, however Cosmos are going to have to go there and see for themselves if there is spodumene exposed.
