The lignite is found below the surface, covered by layers of gravel, sand, or clay, which first need to be scraped away. These top layers are called the overburden.
يكمن اللِّڠنيت تحت سطح الارض ،‏ وللوصول اليه ينبغي ازالة طبقات الحصى ،‏ الرمل ،‏ او الطين التي تغطيه .‏