Ann: December 2018 Quarterly Activities Report, page-30

Clearly you are investing long term rather than short term.
Long term, Eshmun's comments are pertinent and you have to consider whether NST knows more than Eshmun and so can deliver the amount of gold from its mines at an AISC to justify its share price going forward, over an extended period.
Short term, subject to movements in the gold price, NST is likely to decline in price as a result of the latest announcement, which I believe shows it is clearly over-valued compared to other major AU gold producers.
Of course, whether short or long term, NST has been considered a darling of the AU gold producers and so has been priced high for some time. Will that continue? Who knows? My opinion is that we are entering the realm of market psychology here and I am only a stay at home type of guy with a spreadsheet for analysis and internet access for information. I am often happy to buy when the market trounces a stock because it overshoots but I keep away when it shows signs of being over-valued. I do not consider NST a buy at present but you need to make your own assessment along with everyone else because this is only my un-professional opinion.

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