Hand wash only.
Because it is a porous and natural material without any coating, volcanic stone will darken or stain when in contact with foods and oils.
The Tzalam wood lid finishing is chemical free. Wash with water, soap and dry immediately. Being a tropical wood,it is recommended that you hydrate with linseed oil, coconut oil or beeswax to avoid dryness and cracking, caused by climate change to their natural environment. It is normal that spots and cracks can appear due to use, climate change and contact with some oils.