Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Alexandre Brongniart and René Just Haüy
From Greek trakhus rough’ or trakhutēs roughness
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
Teschenite is coarse- to fine-grained, dark-coloured intrusive igneous rock that usually occurs in sills, dikes and irregular masses and is always altered to some extent
From its occurrence near Teschen. now known as Cieszyn, Pol., Scotland
Coarse Grained Rock, Opaque Rock