noun, feminine/ɛs.kaʁ.bij/plural: escarbilles
a small piece of unburned coal mixed with ashes; a speck of ember that escapes from a fire and floats in the air; floating ember
“la dernière pelletée d'escarbilles était brûlée depuis la veille”
Ultimately from Middle Dutch schrabben, schrabbelen (see modern Dutch schrapen (“scrape, rake”)).