Julian Cope presents Head Heritage

apparently the irish name for quartz "grianchloch" means sun-stone. so their aparent sun worship would explain the findings of 'sun-stones' at these sites. But how and why does quartz represent the sun? sun is power, quartz being the hardest thing known to the ancient peoples then maybe thats why the granite is there too, granite being the hardest rock to hand, both symbolise strength and power. or because they wanted thier monument to last forever...