hard form of quartz

FLINT
List of words for the clue hard form of quartz from the crossword:
AGATE ONYX SARD SILICA JASPER CRYSTAL TOPAZ GLASS MINERAL TIGERSEYE SILEX SSN OPAL GEODE AMETHYST UNI SEIKO SARDS PRASE ONYXES
WordClue
NUThard-shelled seed
RAPsharp blow with something hard
BRANhard outer layers of cereal grain
DISCcompact or hard
LIEDmusical form
RIOTform of civil disorder
BLUESmusical form and a music genre
COLICform of pain
FUGUEmusical form
GLASSmagnifying or quartz
NEXUSform of connection
SHELLhard external covering of an animal
HELMEThard hat
TATTOOform of body modification
MINERALbauxite or quartz
AMETHYSTquartz variety
PRINTOUThard copy
SYMPHONYform of classical music
ADVERSITYhard life
STRETCHINGForm of physical exercise
SHELLhard external covering of an animal
HELMEThard hat