 The Incapillo ignimbrite contains xenoliths with sizes of 0 @.@ 5 – 4 centimetres ( 0 @.@ 20 – 1 @.@ 57 in ) formed by amphibolite . Amphibole crystals are enclosed in intersitital plagioclase crystals and sometimes contain secondary biotite crystals . Amphibole is the dominant component . 
