— hypersthene of N. York, L. C. Beck, xlvi, 35.
— idocrase, T. Richardson, xxxviii, 120.
— indigo, xviii, 241.
— iolite, xlvi, 383.
— iron, supposed native of Bedford Co. Pa., xiv, 183.
— iron ore of Pennsylvania, W. R. Johnson, xxxviii, 383; xxxix, 142.
— iron ore, bog, in New Jersey, H. Seybert, viii, 298.
— iron, native phosphate, of Cornwall, vii, 369.
— iron, titanic, of Baltimore, T. G. Clemson, xvii, 42.
— isopyre, xv, 388.