I think thats right Esh. If holders want to track the most recent descent into amateur hour then start with the announcement on 18 Dec 17 (all quotes below are from that announcement - but most announcements after that one also contain statements demonstrating poor technical knowledge).
18 December 2017: "This small hammer mill is achieving recoveries of over 90% and grades ranging between 30-149g/t”
Metallurgy 101: Process circuits consist of 2 main components: a comminution circuit (crushing and grinding) and a recovery circuit. A hammer mill is a component of the comminution circuit and doesn’t recover gold, it mills it. A mill also doesn’t ‘achieve grades’, it mills whatever ore is put into it after which it needs to go somewhere else to recover the gold from the milled ore.
"this compares with the existing gravity plant that has been achieving recoveries of 73-80% and an average head grade of 1.6 to 2.1 g/t”
A hammer mill or any other mill/crusher can’t be compared to a gravity circuit. They are completely different things that perform completely different functions. Metallurgy 101 part 2. Head grade is the grade of the ore that is fed into a circuit. Head grade is completely independent of and unaffected by whatever circuit it goes into. To imply that a mill or crusher of any sort has any impact on head grade is , well to put it politely, dumb.
"….too early to determine if a much larger hammer mill will show similar recoveries…..”
Again, mills dont recover gold, they mill ore.
“Tests ….have shown that recovery and grade can dramatically improve when it is not sent to the gravity recovery plant”
Where to start with this one? Grade improves? Wow, so you put whatever head grade into the circuit and the grade improves if you use a hammer mill? I could begin to understand what they meant if they said that they get higher recoveries when the ore is more finely milled but they are saying that recovery and grade improve …. Wow - patent that one and call it the Midas machine. They must be still sending the milled ore to some sort of gravity recovery circuit, so they probably meant to say that they are seeing improved recoveries from sending the more finely ground material from the hammer mills to a different/modified/new gravity recovery process.
“This compares with the existing gravity plant that has been achieving recoveries of 73-80% and an average head grade of only 1.6 - 2.1 g/t”
Moving on from the already discussed point that the head grade of ore fed into a circuit is an input not an output and to imply that any circuit has an impact on head grade is wrong, dumb and…. **just shakes head**
Metallurgy 101 part 3. Gravity gold recovery profiles for different grade ores are not linear. Given exactly the same circuit, you do not get the same gravity recovery from ore containing 1g/t au as you will from 30g/t material. To compare recoveries from mill feed that differs in head grade by over 1000% would be incomprehensible to any first year metallurgy student…. And yet, here it is in an ASX company announcement. You can see the actual impact that grade has on cascavel ore recoveries in numerous independent third party tests in announcements released before 18 Dec 2017 (the most recent detail was 5 sept 17).
To then compare the results of processing from August to November 17 to the results from the program being announced and imply that you get a better ‘ grade' from the hammer mill perpetuates the complete nonsense that the hammer mill has any impact on ‘grade'.
Various other statements such as ‘too early to tell if a larger hammer mill will show similar recoveries “ are peppered throughout this and subsequent announcements.
Sure, some of you might say, 'these are just misunderstandings and we know what they are trying to say’. Well ok, but this is a board announcement from a listed mining company that is at best characterised as extremely sloppy in its communication and at worst demonstrates a failure to understand the absolute basics of processing gold. If they dont understand how the process works and what the terminology means then how are they providing adequate oversight and what else dont they understand?
So, I wish all holders luck working out if the tailings grade is ~0.5g/t (7 December 2017 announcement or ~9g.t ( January 2018 Ann) and if the company raised 12m cash or 8.6m cash (23 March) and if the company is entitled to 100% of the gold production ("For clarity, Orinoco takes 100% of all gold production now and going forward” 23 March) or 80% (p62 of the recent annual report).
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