I have tried to do a rough estimation as to how much Graphite...

I have tried to do a rough estimation as to how much Graphite exists at Kookaburra Gully Extended.
The target of 22-44M tonnes @ 10-15% from previous announcements is pretty realistic. Thats 2.2M to 6.6M tonnes of contained Graphite.. or 44 Years to 132 Years of Graphite if you mine it at 50,000 Tonnes per annum. As for the existing holes, there are now 144 of them.
Difficult to know what they could put down as an inferred resource at KGE as the drilling is patchy, widespread and much remains undrilled
An inferred resource however is likely to be very considerable already.

From a 2017 announcement
"Kookaburra Gully Extended
Imagery from the Koppio-Kookaburra Gully airborne EM survey shows that the Kookaburra Gully
deposit is located on the northeastern end of a 4.5 kilometre long series of EM anomalies (Kookaburra
Gully Extended). Based on interpretation of EM data and the size, amplitude and known Mineral
Resources of the Kookaburra Gully and historic Koppio Graphite Mine EM anomalies, which both
contain high-grade graphite deposits, the Kookaburra Gully Extended EM anomalies potentially define
a large zone of graphite mineralisation. Kookaburra Gully Extended has a combined Exploration
Target of 22 million to 44 million tonnes at 10-15% total graphitic carbon (TGC) in the immediate area
(see Lincoln Minerals Limited ASX Announcement 30 January 2014).
It is emphasized that Exploration Target tonnage and grade estimates are entirely conceptual in
nature since there has been no drilling in the immediate area of this target and it is uncertain if
exploration will result in the estimation of a Mineral Resource.
Lincoln has planned a comprehensive exploration drilling program across these EM anomalies with
the aim of defining additional graphite resources."