Question

The original rock from which Gneiss formed is-
(a) limestone
(b) shale
(c) granite
(d) quartzite​

Answer 1

Answer:

its metamorphic rock

Explanation:

The light coloured crystals in gneiss are usually quartz or feldspar, the dark coloured crystals are mafic minerals. How was it formed? Gneiss is formed from another metamorphic rock called schist, which itself started out life as a sedimentary rock called shale

Answer 2

Answer: Granite

Explanation: Gneiss is a high grade metamorphic rock, meaning that it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of granite, or sedimentary rock. Gneiss displays distinct foliation, representing alternating layers composed of different minerals.