Ann: West Arunta Project - Luni Assay Results, page-537

Thanks, good to know this.

Always a problem how to handle core loss in weathered zones (especially, as generally more obvious in fresh rock most of the time).

Agree, within reason, there has to be a way to handle these, not uncommon, issues to JORC standard.

When I was adding the assays to my database I did notice the core loss column. First time presented, I think, and had to add a column.
Took a look at the data and made a subset from >=2.7m of loss.

Treat the results in these zones as a best guess. They will be high with some degree of uncertainty even with triple tube drilling - PQ/HQ/NQ?? Most likely HQ to fresh rock IMO but that is a guess.

	hole	from	to	interval	Nb2O5	phosphate	m%	core loss
1	LUDD23007	66	90	24	3.22	2.8	77.3	7.3
2	LUDD23007	66	101	35	2.22	9.8	77.7	8.5
3	LUDD23007	105	169	64	2.09	10.8	133.8	10.4
4	LUDD23007	126.6	166.7	40.1	3.19	3.3	127.9	7.7
5	LUDD23008	56	74.9	18.9	0.92	10	17.4	5.7
6	LUDD23009	43	62.3	19.3	1.3	3.6	25.1	8.4
7	LUDD23010	79.7	120.3	40.6	0.75	23.1	30.5	5.2
8	LUDD23014	93.6	116.2	22.6	3.77	10.9	85.2	11.0
9	LUDD23014	93.6	123.4	29.8	3.07	9.8	91.5	14.5
10	LUDD23015	60.7	90.7	30	1.05	12.1	31.5	6.1
11	LUDD23015	97.4	199	101.7	0.46	4.2	46.8	12.0
12	LUDD23017	83	128	45	1.18	4.6	53.1	2.7
13	LUDD23017	145	170	25	0.46	12.1	11.5	3.6
14	LUDD23021	46.5	61	14.5	2.51	11.4	36.4	5.0
15	LUDD23021	46.5	121	74.5	0.72	10.7	53.6	5.2
16	LUDD23026	55.4	132.4	77	0.67	6.8	51.6	12.6
17	LUDD23027	87.8	113	25.3	1.55	10.8	39.2	6.7
18	LUDD23027	87.8	136.5	48.8	1.16	8.8	56.6	14.8
19	LUDD23027	126.8	134	7.2	1.28	4.4	9.2	4.4
20	LUDD23032	90	149	59	1.4	11.1	82.6	9.5
21	LUDD23033	112	131.9	19.9	2.15	6.3	42.8	13.5
22	LUDD23035	53.5	77.1	23.6	10.3	11.2	243.1	6.1
23	LUDD23035	53.5	119	65.5	3.33	6.4	218.1	6.2
24	LURCD23042	119	160	41	0.64	27.4	26.2	4.7

Intersections beginning >100m down hole are likely to be approaching fresh rock. Still getting core loss at these depths! Water table/influx? near contact weathered/fresh?

Ah the joys of drilling in challenging environments. Leaving it to a younger generation...

Personal experience of massive core loss and a lot of rubble. How to assign intervals? Was it even worth it for this zone? Au was target rather than Nb/REE which did make decisions less critical.


Palaeochannel country in this image vs a more consistent(?) weathered profile above fresh carbonatite.

Hope the WA1 core didn't resemble this too much.

Sonic drilling test will be interesting as it can do well in unconsolidated/soft material. Never dealt with it but did see good recoveries from a tailings facility once.