With the Teamson Home Brown Lava Rocks, you can create a unique effect and a great conversation piece for your gas fire pit! Rocks sizes range from 1cm to 3cm in diameter and are mostly brown with hints of grey and red. All fire rocks feature a rough volcanic surface. Rocks are all-natural and durable, withstanding temperatures up to 1472F 800C and natural weathering and will not melt, break or emit smoke when burned at high temperatures. Replace any current ceramic logs with lava rocks for a distinctive look for your fireplace or fire pit.