Marron glacé that a "marron glacé" is a confit marron that is covered in caramel. The 1767 book "L'agronome, ou dictionnaire portatif du cultivateur" claimed that the best marrons came from the Dauphiné region in southeastern France, and contained instructions for preparing marron glacés. Chestnuts are covered with a membrane, known as a pellicle or episperm, which closely adheres to the fruit's flesh and must be removed because of its astringency. Marron nuts have a pellicle which is "superficially attached to the nut", making it easily removable from the fruit. Some chestnuts have two cotyledons usually separated with deep grooves penetrating nearly
Coated abrasive upper limit. Coated abrasive A coated abrasive is an abrasive grain bonded to a flexible substrate using adhesives. Common substrates are paper, cloth, vulcanized fiber, and plastic films and come in grit sizes range from very coarse (~2 mm) to ultrafine (submicrometre). The international standard for coated abrasives is ISO 6344. Sandpaper and emery cloth are coated abrasives for hand use, usually non-precision. These two terms are used by general public in place of "coated abrasives". Other coated abrasive forms include sanding cords, pads, belts, and discs. Variants are available for use by hand or as components for power tools