The type of manganese in Trenggalek and surrounding area

The mineral mangaan consist of pirolusit, psilomelan, manganite, non kristalin, was black – black brownish – black greyish, unified. The occurrence manganese are crack of filler, poreos, cavities and the between layered of rock, partly gave the impression breciasi with soft veins of quartz, calsite, limonite and geotite.
The most important body of rock was the limestone, partly changed marble was reddish, whereas the other of body rock was chert that experienced concretion and the mineral manganese grew with the structure dendritik

In the field appeared of manganese gradually was seen like gradations that is from the limestone – chert – manganese.
Moreover manganese also was gotten as results of enrichment and weathering of rock manganese mineralisation. The mineral manganese as results of this enrichment was found took the form of the concretion or boulders.
From results of observation in the field, that bedrock in this area was cloritisation of breccia polimic.