RE:Newlox's Cyanide Use in Costa Rica - A Global Contradiction Thank you for, finally, providing the source of your quoted paragraph. Now if you could either admit you wrote your post to appear as if it were a news source or provide the link to it as well please? I'm not going to hold it against you beyond ensuring by your admission the kind of full disclosure debates like these should have. It could be as simple as saying 'it was a mistake to present it like that' and everyone can move on.
I took a read through the now-sourced technical paper. Unless I'm reading it incorrectly (and I suggest you check dear reader), the paper goes through gold recovery percentages for a variety of processing options: gravity concentration, flotation, and cyanidation. It is noted in the abstract that the use of cyanide is not allowed in Costa Rica. The cyanidation test appears to be a comparator test in this paper with the primary focus being on gravity concentration and flotation. In fact, the technical study states as much by noting that the gold concentrates are to be sold to a processor off-site in Nicaragua and that the plant Newlox was commissioning at the time utilizes only gravity concentration and flotation. I've provided the relevant quotations here:
From the Abstract:
"Although the use of cyanide is not allowed in Costa Rica, the cyanidation of the concentrates with grinding resulted in 87% gold recovery in 12 hours of processing. The idea is to transport the concentrates 200 km to Nicaragua to be leached with cyanide."
From the Conclusion:
"Newlox Gold Ventures Corp. established an initial reclamation centre in the fall of 2014 and, in 2015, is building its processing capacity with the objective or running at a commercial throughput of between 60 and 80 tonnes per day. Gold and mercury recovery are being accomplished through a combination of gravity and flotation concentration and the initial results are promising."
I'd also like to point out that from my untrained eye the flotation process in particular appears to be at least on par with that of cyanidation having a recovery rate of upwards of 91% of gold, with a mass recovery of 23%, compared to 87% after 12 hours of processing time for for cyanidation. Presumably though the concentrate produced from flotation requires further processing to isolate the gold entrained in the concentrate.
The technical report published on SEDAR on January 21, 2016 entitled
Technical report (NI 43-101) - English (Thank you for providing the date for ease in tracking it down Newloxlurker), states that at the time of the report the only processes being used by Newlox at the pilot plant are gravity concentration and flotation which is in line with the disclosure in the concluding paragraph of the 2015 technical study.
So here's where I get to admit I'm wrong. Beyond that first reference I found for the use of the Merrill-Crowe process, which would imply a process of cyanidation being used at the plant, I can't find it ever mentioned again. I can only conclude that they do not appear to be using this process to extract gold from the concentrate at the pilot plant and I was wrong in saying this was the case. Frankly, I was so happy you stumbled so hard over your misunderstanding of the process I didn't look into it much further for a few too many posts. But looking now, instead I see many references to gravity concentration and flotation in addition to a Carbon-in-Leach process and electrowinning used to deposit the gold on the stainless steel cathodes but nothing for Merrill-Crowe thereafter. What the reagents are for the Carbon-in-Leach process remains unclear and is something worth actively looking into. At this point, until I'm confident in what process exactly they are using I won't be commenting on it further.
I would continue to note though that the company's most recent news release states all chemicals necessary for the extraction of gold and silver from the concentrate are fully permitted and in accordance with existing mining codes for Costa Rica. That's a solid, legally binding statement directly from the company. Bad blood between us aside, you need to present some kind of proof of illicit use of cyanide for your argument to be more than just hearsay Newloxlurker.
Just for your reference, here is a resource you can use to get a sense of trade of various goods between nations. As you can see, some 184 tonnes of sodium cyanide were imported into Costa Rica in 2019 so it's not exactly a blanket ban on cyanide. Just something to keep in mind when you keep digging.
Also my prior post linked an article entitled
Death Dressed in Gold which had a curious quote from Director Ileana Boschini about the use of cyanide in gold recovery. She was, and so far as I can determine still is, the Director of the Directorate of Geology and Mines in Costa Rica. See the excerpt below.
***
From her office in San Jos, DGM’s director Ileana Boschini tells me in a phone interview that right now the institution is still conducting research on the best alternatives for processing gold. “Don’t you think you are starting this process late,” I ask her. “Yes, many years went by. It wasn’t until this administration that there was interest in bringing order to many things, but the resources are very limited,” says Boschini, who has been in the job for two years. She adds that the institution believes that cyanide is a better alternative for processing gold. “Despite the fact that is a delicate substance to handle, it’s not as dangerous as mercury.” With mercury, miners recover less than 40 percent of the total gold inside the material, while with cyanide they can recover as much as 90 percent. But in order to use cyanide procedures, special and expensive equipment is required that will be difficult for the cooperatives to purchase. “They are trying to form a consortium to see if they can build a large cyanide processing plant. If they continue with that spirit, the interest of joining forces to have a single plant could be successful,” Boschini says. “Is it realistic to think that, by next year, you can change the technique?” “It all depends on the capital they have,” she says. ***
Finally, and rather unbelievably I know, I've actually got a more important matter that has come up needs my attention going forward for a while. Take that as you will. But I will be paying attention when I can to see if you do bring real evidence to the table. Seriously, good luck in your search.