I check craig's list every day, just so I can flag... while always keeping an eye out on a decent spare cage... I was just curious why her/his fur looked that way... is it only from not being dusted?...
This is what mats can look like on a chinchilla. It's where large chunks of fur form from not being dusted enough. They can get really bad and take up large amounts of the chinchillas fur. It's basically the same thing as when a dog or cat gets mats in their fur.