GRADE AND TONNAGE MODEL OF LATERITE-SAPROLITE Au

By James D. Bliss
COMMENTS Deposits with data are few and likely subject to revision. Most of the data for laterite-saprolite Au deposits are from one area, and this may bias the model. Deposits are under active investigation and have the following qualifications: (1) data on deposit sizes and grades are for unworked deposits, (2) deposits may be underlain by unrecognized mineral deposits in the bedrocks, and (3) deposits may be placer deposits, not laterite-saprolite Au. One such deposit (Omai, Guyana) has residual mineralization at the surface and mineralization in the bedrock and is excluded in conformance with the descriptive model. The general pattern in the mining of mineral deposits is that the total tonnage (production plus reserves) continues to increase over a portion of the mine life. Therefore, deposit tonnages used in the model are very likely minimum values when compared with tonnages at deposit exhaustion. See appendix B for locality abbreviations. See introduction for explanation of the grade and tonnage model as shown in figures 33 and 34.
Figure 33. Tonnages of laterite-saprolite Au deposits.
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Figure 34. Gold grades of laterite-saprolite Au deposits.
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DEPOSITS                          DEPOSITS
Name               Country         Name                  Country
Akaiwang          GUYN        Millionaire             GUYN
Arakaka            GUYN        Mt. Gibson           AUWA
Baramita           GUYN         Royal Hill Gold     SRNM
Boddington       AUWA         Tassawine            GUYN
Bullabuling        AUWA