This is as clear as it gets, page-115

Pegmatites are part of a complex intrusive system. There are a host of factors that dictate presence or absence and abundance of minerals that might be of commercial interest - melt source, tectonic setting and chemistry of associated intrusions, distance from 'fertile' intrusion, fluid pathways etc.

For me there are a couple of red flags in the June 23 announcement about Zola.
1. Mention of muscovite. Pegmatite bodies carrying abundant muscovite are typically poorly mineralised. Samples still need to be collected as you can never be sure, but bear in mind that any Li mineralisation in musovite-rich pegmatites is more likely to be in the form of a mica (e.g. lepidolite, zinnwaldite) than in the pyroxene spodumene.
2. Highly anomalous levels of rare earth metals. Rare element pegmatites are subdivided based on composition in to LCT (lithium-cesium-tantalum) and NYF (niobium-yttrium-fluorine) types. Simplistically, LCT pegmatites host lithium mineralisation and NYF pegmatites host rare earth element mineralisation. So suggesting anomalous levels of rare earth metals is indicative of an LCT pegmatite (as per the CXO announcement) is not correct. However, the LCT-NYF distinction is not clear cut as there are also 'mixed' type pegmatites (indicative of mixed melt source) that have chemical characteristics of both classes.

Finally, the fact that the pegmatite is 'decomposed' is not a good sign for the preservation of spodumene (if present) or for high Li grades at surface. Typically, spodumene breaks down to clays during the weathering process and Li is lost to the environment.