Agate geode weighing in at 1½ kilos, a hefty piece of rock which boasts fascinating banding and sparkling quartz crystals. Its highly polished surface has a vitreous lustre but to be fully appreciated the geode either needs to be placed up at eye level or needs to be tilted back slightly as the base of the rock is completely flat.
Being a relatively hard mineral which grades 7 on Mohs scale of mineral hardness makes agate an ideal lapidary material and it's known to have been used for this purpose for thousands of years. Best known for its characteristic curves or angular bands, agate is a type of chalcedony which in turn is a cryptocrystalline variety of quartz. It's mostly translucent and exhibits more than one colour but due to these often being neutral colours like greys and whites, agate is often dyed which apparently makes it more attractive to the wider commercial market. That said, many agates can display spectacular colours which are caused by impurities such as iron, manganese, titanium, chromium and nickel.
Weight (grams): 1460
Size (cms): 15.6 x 8.7 x 8.9