I use the formula mentioned above and valued CRK based on that....

I use the formula mentioned above and valued CRK based on that. They should be $4.28 a share with their 4 million+ ounces and open cut mineable grades, yet the market currently values them at 65c a share or around $18 an ounce! Let's face it the market is not rational. It's a very tightly held company with two shareholders, including the CEO, holding about 57%. I can't comprehend their current valuation perhaps someone can enlighten me!
What a company is actually worth in reserves and what the market values it at are not the same thing. From my experience one cannot anticipate a share price based on reserves. Sentiment is also important. Good promotion and exciting announcements can take a share price above the actual worth of the company. I know of one such company which is overvalued but well promoted.
The point about needing a million ounces and grades of 2gm or better to be cost effective to mine might be worth taking into account.
It looks as though gold may be due for a very significant rise even from these levels as the US dollar is shunned, so there may be a rush for shares in some of the laggards. I guess we'll have to wait and see.