Rare deep purple spirit quartz cluster

This is a rare deep purple spirit quartz cluster from Boekenhouthoek, South Africa.  Most spirit quartz is found in light purples, yellow citrines or white. The rarest kinds found to date are deep purple, and even rarer still, smoky, almost black spirit quartz. This piece measures approximately 10 cm x 7.5 cm x 6.3 cm and weighs 420g.