Your mining engineer or mining geologist will be able to obtain additional information. He may check the indexes of dissertations and theses and find some that are relevant to your ground. Hard copies can be obtained from the Xerox University Microfilms, P.O. Box 1346, Ann Arbor, Michigan, 48106. Your experts may he able to add to your knowledge by consulting the various libraries at universities and mining schools.

          The professional publications of the Society of Mining Engineers of A.I.M.E. (American Institute of Mining and Metallurgical Engineers) may have material relevant to mining methods or recovery processes that would be to your advantage.

          Frequently, in a lode claim there are outcrops exposed on the surface and from surface work you can obtain two dimensions of your deposit. You can measure the length and width of the vein at the surface. It is desirable to have a third dimension to calculate the cubic tons. It is better to spend your money drilling or digging shafts or pits to obtain this third dimension than to spend it on legal fees in a contest later on.

          In a gold placer deposit, you can usually measure the length and width of the auriferous alluvials on the surface. The third dimension may be determined sometimes by geophysical methods. Cross sections can be mapped from these data. We are told by a U.S.G.S. Circular that underground placer strata can be measured within ten per cent of accuracy.

          If you can show that your lode or placer is suitable for in situ leaching or heap leaching at a lower cost than other methods of mining, you may prove lower costs and higher economic potential. The Bureau of Mines will help you. If you write to the United States Bureau of mines, 4800 Forbes Avenue, Pittsburgh, Pennsylvania, 15213, they will send you a bibliography listing over 160 sources of information about in situ leaching. ²⁶ William C. Larson, Geologist, and Dennis B. Dandrea, Geophysicist, at the Mining Research Center, U.S. Bureau of Mines, are available for consultation.

          The "Field Handbook for Mineral Examiners" of the U.S. Department of the Interior, Bureau of Land Management, should be consulted. Use the references listed in the Handbook. One of the texts mentioned is McKinstry's "Mining ²⁷ Geology”. The section on geologic principles of ore search is important in establishing geologic inference.

          Geologic inference alone is not acceptable to prove a valuable mineral deposit, but it is acceptable as proof when mineral has been exposed physically on the ground.
There are different kinds of mineral examination described in the Mineral Examiner's Field Handbook. The BLM. Manual release #3-41 describes the type of mineral examination that must be made in connection with a mineral patent investigation. This examination is primarily to verify what has been said in the patent application and supporting proofs.