I'm guessing from the information that they presented earlier in the year. Here is some info that caused me to half draw the conclusion:
The speed at which MCR could JORC up their resources tells me that there has been some historical work sitting on the shelf. The gold zones appeared thin and horizontal, although there were quite a few of them. From the announcements, it appears that some pit mining has already taken place. This pit mining must have been halted at some stage due to a lack of profitability.
So, my guess is that the gold is there, although, in the past it wasn't profitable to mine it. With the gold price at near record highs (and heading higher?), it's possible that this gold may now be profitable, so MCR has pulled the old records off the shelf, dusted them off, and JORCed up some gold. I'm sure that someone else can give better analysis of the profitability of this gold than me, so I'll leave it there.
Ni is looking good anyway, so the gold might stay where it is... who knows?
MCR Price at posting:
36.0¢ Sentiment: None Disclosure: Not Held