Article Nº 1797 Geology and mineralogy Vol. II · p. 241
Hypersthenite
Original title: Hiperstenite
Notes Johnson's report of hypersthenite rock at Porto da Cruz, which later geologists have not confirmed; Gagel identified essexite and madeirite there instead.
Johnson records this rock, which belongs to the diabase group, at Porto da Cruz (‘harbour of the cross’), but his discovery does not appear to have been confirmed by the observations of the modern geologists who have visited the locality. In Gagel’s view, essexite and madeirite occur there, rocks which probably correspond to Johnson’s hypersthenite. See Geology.
Places mentioned