RE:Book value of TV Arturo, book value does not mean much in mining. Firecracker would know better than I do, but I think book value is mostly what the company has spent on the mine, processing plant, and equipment. In other words, it is the capital that has been spent to create the mine. It does not really tell you the value of the metal in the ground. In fact, book value is kind of a liability because it must be depreciated, and it works against earnings (yes, on a non cash basis for people who think cash flow is more important than earnings).
I doubt Trevali's book value has changed much over time. As capital items depreciate, they are usually replaced by new capital spending.
What matters a lot more than book value is the amount of profit the mines can generate given expected metals prices. Starting in Q2, Trevali should be a profit machine. If you think the price of zinc will stay elevated, Trevali will probably be able to earn back its entire market cap in about 3-4 years.
As for the price of zinc and the price of Trevali stock, here are the charts.