An article presented hereby relates to valuation of undeveloped deposits of minerals which are not sold on markets in unprocessed form and their processing into a marketable commodity calls for construction of an additional plant which usually is not operated by a mining company. In practices lignite and limestone deposits fall into the above defined category. Difficulties in their valuation are caused by their two major properties: any economically justifiable development of such deposits can be carried out only in close co-operation with a neighboring power plant or cement factory and development of such fields is usually lengthy. Therefore, out of four methods recommended by the POLVAL Code to be used for valuation of undeveloped mineral deposits only the options based approach seems to offer, however with some important limitations, useful tools for appraisal of lignite and limestone deposits.