The 99.9% is no surprise at all as it stems from ion-exchange....

The 99.9% is no surprise at all as it stems from ion-exchange. So the ion-exchange just does what it is supposed to do.

What is really fascinating is the processing time (hours ilo months) and the statement of "having globally competitive production costs of US$2,600/tonne (+/-30%), which is in the lowest cost quartile for lithium carbonate production, using a commercial-sized Lilac Solutions production plant. (Note: The estimated costs of production are preliminary estimates based on the Phase 1 Engineering study.)" - source: lilacsolutions.com

Of course this is the IP of Lilac (and I would love to buy their stock if they were listed), but LKE obviously would be the first applicant.
Exciting times ahead...