Riddle
It's a thing
You hold it when you use it
It is colorful
It may be found on a desk
It's probably made of plastic
It doesn't have face
It sometimes burns
It sometimes gets really hot
It sometimes produces heat
It produces light
I doubt that you give it as a gift
I doubt that you use it at work
It contains liquid
It's sometimes black
You can't open and close it
It can fit in an envelope
Do you give up?