326 New York State Museum 



occurs at the base of the Williamson shale (the Wolcott 

 Furnace ore bed). Another ore bed is also present in 

 the basal Sodus shale (Sterling Station ore). The ore 

 continues east of Wayne and Cayuga counties and is 

 found in the Clinton section where the highest ore bed 

 occurs. This highest bed is found at the base of the 

 Rochester shales and sandstones and is the "fossil" ore, 

 and the only one that has properly been so named. The 

 "oolitic" ore bed at the base of the Williamson shale in 

 this section is the next older and the only one now mined 

 at Clinton. The iron ore of the Clinton is hematite and 

 is" always red in color. It has been variously termed "fos- 

 sil iron ore," because of the replacement of fossils such 

 as crinoids and bryozoans by the iron ore, and "oolitic" 

 or "lenticular" ore, because of the presence of lenticular- 

 shaped spherules in the ore. Mines are located in On- 

 tario, Wayne county, Sterling Station, Cayuga county, 

 and near Utica in the town of Kirkland. 



Above the Reynales limestone in the Rochester sec- 

 tion is an 18-foot bed of purple and olive shales with 

 thin plates of fossiliferous limestone which has received 

 the name Bear Creek shale (Chadwick T9) from ex- 

 posures along Bear creek, near Wolcott. The pearly 

 lustre is due to shells of the exceedingly abundant 

 brachiopod Anoplotheca (Coelospira) hemispherica. Also 

 in the shale occur fairly characteristic pelecypods as 

 Modiolopsls subalata, Orthodesma curtum etc., a trilo- 

 bite, Phacopidella trisulcata, and well-preserved ostracod 

 valves of which the most important are five species of 

 Zygobolba (Z. antic ostiensis zone). This formation has 

 a thickness of 20 feet at Wolcott, and pinches out before 

 reaching Lakeport. These shales have been included 

 with the overlying dark graptolitiferous shales in the 



