(1) The lease shall be granted on the standard lease form for a primary term or period of 10 years, and as long thereafter as metalliferous minerals or gems in paying quantities are produced, on condition that all royalties, rents, and other obligations are fully kept and performed by the lessee. The board shall extend the term of the lease if it determines that a failure to produce in paying quantities is a result of factors beyond the control of the lessee such as but not limited to a national emergency or a temporary decrease in the price at which the particular metalliferous mineral or gem can be sold.