Agate

Agate is an opaque stone with banded, concentric shell-like chalcedony species (microcrystalline of quartz family). The bands can be multicoloured or of the same colour. The name agate was given by Theophrastus, a Greek philosopher and naturalist, who discovered the stone along the shore line of the river Achates (now called the Drillo) in Sicily.

Agate are often found in ball or almond shaped nodule mass, when cut open, it reveal a variety colour and pattern bands. Agate bands are thought to be formed by rhythmic crystallization or crystallize gradually in hollows forms by gas bubbles from a siliceous solution and slowly filling the cavity of the host rock.

Types of Agates

Eye Agate

Ring-shaped patterns similar to an eye.

Layer Agate

Layers/bands are parallel to the outer wall of the agate nodule.

Dendritic Agate / Landscape Agate

Colourless or whitish, translucent contains black or brown tree-like (dendritic) inclusions; the inclusions are caused by iron oxides and hydroxides.

Fire Agate

Opaque, oily bubbles bearing layered with iridescence which is created through diffraction of the light by the layered structure. The oily bubbles bearing layer is caused by light diffraction through layers of iron oxide within the quartz.

Moss Agate

Translucent agate, with black, brown or greenish moss-like inclusions. The black or brown inclusions are caused by black or brown manganesse or green chloride.