Grape agate refers to a type of chalcedony that is known for its distinctive appearance, resembling a cluster of small, grape-like spheres. The proper mineralogical term for grape agate is "botryoidal chalcedony." Botryoidal refers to a rounded, globular, or grape-like formation. It forms through the concentric growth of chalcedony around a central nucleus. This process results in the characteristic grape-like clusters of small, rounded structures. Chalcedony is a type of microcrystalline quartz. It often occurs in massive form and is composed of tiny quartz crystals. When chalcedony forms in botryoidal shapes, as seen in grape agate, it creates a unique and visually appealing texture. APPROXIMATE DIMENSIONS Height : 33 cm Width : 10 cm Length : 9 cm > THE WEIGHT MENTIONED IS INCLUDING STAND AND PACKING MATERIAL. SHIPMENT - The item will be sent with a Track & Trace code via DHL Parcel, DPD or postNl. The tracking will be updated in your Catawiki lot once your parcel has been dropped off. - Please check regularly to avoid your parcel being returned to us, in which case the buyer will be responsible for the shipping costs of the 2nd shipment. - For tracking to Spain and Portugal please use this link and add the tracking number from your Catawiki lot https://clientesparcel.dhl.es/LiveTracking/Home - WE DO NOT COMBINE SHIPPING!!! - If you have any questions about your parcel please contact us using the Catawiki message service. We will try to reply within 3 working days.