Metalline Mining Company
   News Release: For immediate release August 31, 1999      

Oxide Zinc Drill Results Sierra Mojada Project

 

Coeur d’Alene, Idaho - Metalline Mining Company announces results from 8 additional drill holes at their Sierra Mojada Project, Coahuila, Mexico.  These holes were drilled to test the oxide zinc orebodies in the San Salvador, Encantada and Fronteriza mines.  About 600,000 tonnes of oxide zinc ore, grading 30% zinc, has been direct shipped to smelters from these mines for the past 40 years.  The holes test the oxide zinc system over and east-west distance of 1500 meters and are spaced at about 200 meter intervals.  In addition to drilling, 170 channel samples were collected from stopes and workings in the mines in the vicinity of the drilling.

As previously announced, oxide zinc ore has been mined in the district over a distance in excess of 5 kilometers.  The high-grade direct shipping ore of the San Salvador, Encantada and Fronteriza has been mined throughout a volume of rock 1500 meters by 200 meters by 100 meters vertically, a volume of 30 million cubic meters.  An average 10% grade in only 20% of this volume would be 20 million tonnes of ore and would sustain 5000 tonne per day operations.  Production of 5000 tonne per day with a grade of 10% zinc would make Sierra Mojada the fifth largest zinc mine in the world.  The probability of developing this required tonnage in these three mines is considered to be very good and there is an additional 3.5 kilometers in which to continue to develop reserves. The mineral system continues beyond the mined 5 kilometers to the east and the west and probably to the south.

 

Results:

 

Hole        From                To                Zn                $ Value   Meters

                                                %                per mt    

Metal price $/lb                0.64                                         Average zinc price over the past 35 years.             

R9911     149                150                20.60                290.05    

R9911     150                151                4.98                70.12      

                                                12.79                180.08          2

R9911     167                168                6.98                98.28      

R9911     168                169                4.24                59.70      

R9911     169                170                10.15                142.91    

R9911     170                171                11.60                163.33    

                                                8.24                116.05          4

R9911     197                208                11m no recovery, stope                   

R9911     208                209                11.70                164.74    

R9911     209                217                8m no recovery, stope                   

R9911     217                218                4.00                56.32      

R9911     218                219                1.82                25.63      

R9911     219                225                6m no recovery, stope                   

R9911     225                226                24.40                343.55    

R9911     226                228                2m no recovery, stope                   

                                                10.48                147.56          4              sampled                                

13.28                186.98                Average of 17 samples in workings near this interval

                                                                                31 meter interval

 

Hole        From                To                Zn                $ Value   Meters

                                                %                per mt    

Metal price $/lb                0.64                        

R9911     228                229                3.93                55.33      

R9911     229                230                1.36                19.15      

R9911     230                231                1.92                27.03      

R9911     231                232                1.36                19.15      

R9911     232                233                1.06                14.92      

R9911     233                234                5.36                75.47      

R9911     234                235                1.59                22.39      

R9911     235                236                1.95                27.46

R9911     236                237                1.48                20.84

R9911     237                238                1.32                18.59

R9911     238                239                0.74                10.42

R9911     239                240                0.73                10.28

R9911     240                241                0.44                6.20

R9911     241                242                0.33                4.65

R9911     242                243                1.71                24.08

R9911     243                244                1.33                18.73

R9911     244                245                2.26                31.82

R9911     245                246                2.31                32.52

R9911     246                247                1.53                21.54

R9911     247                248                1.47                20.70

R9911     248                249                4.48                63.08

R9911     249                250                3.67                51.67

R9911     250                251                1.10                15.49

R9911     251                252                0.44                6.20

R9911     252                253                0.31                4.36

R9911     253                254                1.34                18.87

R9911     254                255                2.03                28.58

R9911     255                256                3.21                45.20

R9911     256                257                1.61                22.67

R9911     257                258                1.72                24.22

R9911     258                259                1.29                18.16

R9911     259                260                1.27                17.88

R9911     261                262                0.82                11.55

R9911     262                263                0.34                4.79

R9911     263                264                0.16                2.25

R9911     264                265                0.20                2.82

R9911     265                266                0.95                13.38

R9911     266                267                2.67                37.59

R9911     267                268                5.59                78.71

R9911     268                269                14.35                202.05    

R9911     269                270                14.70                206.98    

R9911     270                271                15.50                218.24    

R9911     271                272                2.11                29.71      

                                                2.65                37.34          43           

R9917     171                172                1.40                19.71      

R9917     172                173                1.34                18.87      

R9917     173                174                1.51                21.26      

R9917     174                186                12m no recovery, no known workings                  

R9917     186                187                1.69                23.80      

R9917     187                188                1.28                18.02      

                1.44                20.33            5

                                                                                    17 meter interval

 

Hole        From                To                Zn                $ Value   Meters

                                                %                per mt    

Metal price $/lb                0.64                        

R9918     157                158                4.12                58.01      

R9918     158                159                5.54                78.00      

R9918     159                160                3.61                50.83      

R9918     160                161                5.48                77.16      

R9918     161                162                0.22                3.10        

R9918     162                163                1.86                26.19      

R9918     163                164                2.61                36.75      

R9918     164                165                2.11                29.71      

R9918     165                167                2m no recovery, no known workings                  

R9918     167                168                2.05                28.86      

R9918     168                169                1.18                16.61      

R9918     169                170                3.72                52.38      

R9918     170                171                1.16                16.33      

R9918     171                172                2.06                29.00      

R9918     172                173                0.40                5.63        

R9918     173                174                11.65                164.03    

R9918     174                175                13.90                195.71    

R9918     175                176                4.24                59.70      

R9918     176                177                2.04                28.72      

R9918     177                178                10.25                144.32    

R9918     178                179                18.90                266.11    

R9918     179                180                16.30                229.50    

R9918     180                181                1m no recovery, no known workings                  

R9918     181                182                11.85                166.85    

R9918     182                183                2.17                30.55      

R9918     183                184                1.48                20.84      

                                                5.37                75.62               24

Within the above interval                                           27 meter interval

R9918     173                174                11.65                164.03    

R9918     174                175                13.90                195.71    

R9918     175                176                4.24                59.70      

R9918     176                177                2.04                28.72      

R9918     177                178                10.25                144.32    

R9918     178                179                18.90                266.11    

R9918     179                180                16.30                229.50    

R9918     180                181                1m no recovery, no known workings                  

R9918     181                182                11.85                166.85    

                                                11.14                156.87               8

                                                                                          9 meter interval

R9919     142                143                14.20                199.94    

R9919     143                144                3.87                54.49      

R9919     144                145                4.74                66.74      

R9919     145                146                3.67                51.67      

R9919     146                147                2.26                31.82      

R9919     147                148                3.11                43.79      

R9919     148                149                1.93                27.17      

R9919     149                150                2.36                33.23      

R9919     150                151                0.37                5.21        

R9919     151                152                0.84                11.83      

R9919     152                153                0.76                10.70      

R9919     153                154                0.94                13.24      

R9919     154                155                2.56                36.04      

R9919     155                156                1m no recovery, no known workings                  

Hole        From                To                Zn                $ Value   Meters

                                                %                per mt    

Metal price $/lb                0.64                                     

R9919     156                157                2.31                32.52      

R9919     157                158                1.64                23.09      

                                                3.25                45.82           14

Within the above interval                                       15 meter interval

R9919     142                143                14.20                199.94    

R9919     143                144                3.87                54.49      

R9919     144                145                4.74                66.74      

R9919     145                146                3.67                51.67      

R9919     146                147                2.26                31.82      

R9919     147                148                3.11                43.79      

R9919     148                149                1.93                27.17      

R9919     149                150                2.36                33.23      

Within the above interval   4.52                63.61            8

R9919     142                143                14.20                199.94    

R9919     143                144                3.87                54.49      

R9919     144                145                4.74                66.74      

R9919     145                146                3.67                51.67      

                                                6.62                93.21            4

R9920     193                194                5.13                72.23      

R9920     194                195                6.98                98.28      

R9920     195                196                7.40                104.19    

R9920     196                197                2.09                29.43      

R9920     197                198                1.56                21.96      

R9920     198                199                3.37                47.45      

R9920     199                200                1.40                19.71      

R9920     200                201                1.93                27.17      

R9920     201                202                1.66                23.37      

R9920     202                203                2.47                34.78      

R9920     203                204                0.87                12.25      

R9920     204                205                0.67                9.43        

R9920     205                206                1.97                27.74      

R9920     206                207                16.35                230.21    

R9920     207                208                17.75                249.92    

R9920     208                209                1.01                14.22      

R9920     209                210                1.41                19.85      

R9920     210                214                4m no recovery, stope ??? do not know                  

R9920     214                215                0.42                5.91        

R9920     215                216                0.19                2.68        

R9920     216                217                1.24                17.46      

R9920     217                218                4.03                56.74      

R9920     218                219                3.31                46.60      

R9920     219                220                4.31                60.68      

R9920     220                223                3m no recovery, stope                   

R9920     223                224                9.47                133.34    

R9920     224                225                17.20                242.18    

R9920     225                226                3.88                54.63      

R9920     226                228                2m no recovery, stope                   

R9920     228                229                14.60                205.57    

R9920     229                230                11.20                157.70    

R9920     230                231                18.90                266.11    

R9920     231                232                7.16                100.81    

                                                5.66                79.75           30

                                                                                    39 meter interval

Hole        From                To                Zn                $ Value   Meters

                                                %                per mt    

Metal price $/lb                0.64                        

R9921     159                160                15.75                221.76    

R9921     160                161                6.30                88.70      

R9921     161                162                20.30                285.82    

R9921     162                163                14.20                199.94    

R9921     163                164                21.40                301.31    

R9921     164                165                12.85                180.93    

                                                15.13                213.08          6

R9922     137                138                21.90                308.35    

R9922     138                139                21.80                306.94    

R9922     139                140                22.10                311.17    

R9922     140                141                11.20                157.70    

R9922     141                145                4m no recovery, stope ??? do not know                  

R9922     145                146                11.40                160.51    

R9922     146                147                4.73                66.60      

R9922     147                148                8.52                119.96    

R9922     148                149                3.18                44.77      

R9922     149                150                3.52                49.56      

R9922     150                151                8.82                124.19    

R9922     151                152                9.01                126.86    

R9922     152                153                8.60                121.09    

                                                11.23                158.14        12

R9923     127                128                5.36                75.47      

R9923     128                129                6.51                91.66      

R9923     129                130                2.09                29.43      

R9923     130                131                4.26                59.98      

R9923     131                132                2.67                37.59      

R9923     132                133                3.37                47.45      

                                                4.04                56.93            6

R9924     275                276                4.92                69.27      

R9924     276                277                3.03                42.66      

                                                3.98                55.97            2

R9924     307                308                4.77                67.16      

R9924     308                309                5.42                76.31      

R9924     309                310                3.25                45.76      

                                                4.48                63.08            3

R9924     337                338                8.59                120.95    

R9924     338                339                16.15                227.39    

R9924     339                340                2.17                30.55      

                                                8.97                126.30          3

 

NOTE:  The above intervals of no recovery are a combination of drilling through stopes (portions of the orebody that have been mined) and unmined portions of the ore zone that are soft and broken and may have voids or vugs.  Consequently no sample is returned until the drill has passed through these intervals.  In the stoped intervals the grade was plus 20%, the minimum grade accepted at the smelters.

 

The 170 channel samples collected from workings in the three mines in the vicinity of the drill holes have an average grade of 14.85% zinc.

Previous mining has been done on the premise that the zinc manto (bed) was a single bed a few meters thick.  The objective of these holes was to test the vertical character of the mineralization over the 1500 meter extent of the three mines.  The results demonstrate that the ore intervals are much thicker than those previously mined and that there are multiple ore horizons or mantos in all three mines.  These results are extremely positive for the probability of developing the 20 million tonne reserve at an average grade of 10% zinc, the threshold necessary for a 5000 tonne per day mine and hydrometallurgical plant to extract refined zinc.