@Aldi99 From the SUM announcement
"The pegmatites contain crystals of Columbite and Tantalite along with associated Tourmaline and Mica mineralisation that are clearly visible in outcrop as dark nodules and veins ranging in size from sub 1cm to 40cm in size."
The veins are 1cm to 40cm in width, what they didn't bother mentioning is how far apart the veins are, as in how many metres of waste rock to get to the next 1-5cm vein, that most of the veins will be.
If I was a shareholder of that company I'd be looking for a liquidity event to dump into, which might be today.. Notice no pictures of the veins, in context of the entire pegmatites, because that would spoil the party.
The above photo is of pegmatites, and the small dark coloured veins in the lower left are the likely niobium/tantalum/tourmaline/muscovite areas. Look at all the white inbetween.
Perhaps if SUM are lucky there will be a lot of spodumene (lithium) in the pegmatites, but if it was there we'd have heard about it already..
The rotary lie detector will sort this one out fairly quickly with whole rock samples being quite low in niobium and tantalum, except for the thin veins.
Artisanal mining works, with the small operators concentrating on just the veins and leaving a huge mess behind, it wouldn't be allowed in Australia. Bulk mining of very hard pegmatites to gain access to the niobium and tantalum which would average down in the 0.3% range if lucky, would be too expensive compared to the mining of weathered pyrochlore (much softer), which is precisely why the niobium mines are carbonatites, not pegmatites.
(20min delay)