Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to [email protected]. Why don’t rocks burn? – Luke, age 4, New Market, ...

Coal forms when swamp plants are buried, compacted and heated to become sedimentary rock in a process called coalification. "Very basically, coal is fossilized plants," James Hower, a petrologist ...

Brown coal (lignite) is a soft brown combustible sedimentary rock formed from naturally compressed peat. It is considered the lowest rank of coal due to its relatively low heat content.

"Coal takes longer to form than any other rock type," says Bailey. Ironically, ... She's a coal geologist, and coal and sedimentary petrologist. Dr Bailey spoke to Kylie Andrews.