Agate is a chalcedony quartz that forms in a wide variety of colours and textures, often in concentric layers. Agate is characterised by it’s microcrystalline structure and brightness of colour. The different agate forms include carnelian agate (reddish hues), blue lace agate, plume agates, moss agate, Botswana agate, fire agate, crazy lace agate/Mexican agate and eye agate among other varieties.