1 - 25 of 2
| Title | Date | Type | ||
|---|---|---|---|---|
| 1 |
 |
The Holt-Dern roasting process as applied to the treatment of lead ores | 1915-05 | Text |
| 2 |
 |
Mining and milling of complex lead and zinc ores in the Park City district, Utah | 1916 | Text |
1 - 25 of 2
| Title | Date | Type | ||
|---|---|---|---|---|
| 1 |
|
The Holt-Dern roasting process as applied to the treatment of lead ores | 1915-05 | Text |
| 2 |
|
Mining and milling of complex lead and zinc ores in the Park City district, Utah | 1916 | Text |