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GEOLOGY AND MINING INDUSTRY OF LEADVILLE. 



Table X. — Various ores and vein materials. 

 N. B.— Witb the exceptions noted, blanks in tbe table denote "no tests." 



1. "Hard carbonate," Scuoper mine, Yankee Hill. 



2. "Silicious ore," El Capitan mine, lajlor Hill. 



3. '-GolU ore," Ore Coll. Xo. 60, El Capilan mine, Taylor Hill. 



4. Silicious bematite. Ore Coll. No. 84, Cbrysolito mine. 



5. "Iron ore," Ore Coll. No. 90, Kenosba mine, Long and Derry Hill. 

 C. Altered limestone {'jigbt material). Garden City mine. 



7. Altered limestone (dark material), Garden City mine. 



8, 9, and 10. Specimen sbowing pyiite altering to a light ocherous mass 

 8. Nucleus of pyrite. 9. Dark zone. 10. Light outer zone. 



11. White filling in chert nodule from porphyry. Ore Coll. No. 300b, Ben Burb abaft 



12. Chert nodule, Ore Coll. No. 299, El Paso shaft. 



13. Breccia with ore cement. Ore Coll. No. 53, Evening Star mine. 



14. Chert under ore body, Little Pittsburgh mine. 



15. Granular quartz under ore, Ore Coll. No. 3a, Waterloo mine. 



Coll. Ko. 44, No Name gulch. Lake Co. 



a Remainder Fe203 and AI2O3, no water. 



h Remainder Fe203 and AI2O3. Of the SiOa 3.06 per cent, was soluble in a moderately strong solution of potassium 

 hydrate. 



c Cementing material chiefly pyromorphite, with some galena and cemssite, also a little calcite. 



d Remainder chiefly PbCOs and FezOj; of the silica 3.93 per cent, was soluble in a moderately strong solution of 

 potassium hydrate. 



e By difference. 



/ Calculated. 



g By difference; includes some PbO and Sb205- 



h By difference; includes a little Sb206. 



i Remainder chiefly SiOa. 



;■ Remainder is SO3 and H20. 



REMARKS ON TABLE X. 



The analyses of the above table were made without view to completeness, the 

 object being in the majority of cases to ascertain merely the general nature of the ore 

 or material under hand. As this appears at a glance from the tabulated results, fur- 

 ther remarks are unnecessary except in the case of 8, 9, and 10. The specimen showed 

 a nucleus of granular iiyrite in process of decomposition, ferric oxide being observable 

 througliout the mass. This very irregular nucleus was iuclo,sed in an envelope of dark- 



