No, the blade of a folding knife should not be used for ignition purposes. The blade of a folding knife is typically made of metal, such as stainless steel, and is not designed or intended for use in generating sparks or flames. Attempting to use the blade for ignition can be dangerous and may result in injury or damage to the knife. It is important to use appropriate tools and methods for starting fires or igniting materials, such as matches, lighters, or fire starters specifically designed for that purpose.