Dated back around four thousand years ago, Qijia Culture covered Kansu, Ningxia and Chinghai Provinces of the Yellow River Areas. The variety of jade artifacts from Qijia Culture is various. Typical jade artifacts from this period are jade knives, zhangs, kweis, bi and congs. Most of the jade artifacts unearthed are found with plain and smooth surface.
A unique feature of Qijia Culture jade artifacts is the uni-directional hole-drilling, resulting in visibly irregular edges. Most of the jade artifacts unearthed are found with plain surface. It is claimed that if a Qijia artifact has motif, then its genuineness is doubtful. Typical jade artifacts from this period are fine carved thin jade knives and zhangs with fine polished smooth surfaces.
就地理區而言, 齊家文化分佈於甘肅, 青海及寧夏,就歷史的長河而言, 齊家文化距今約四千年. 齊家文化玉器種類繁多, 但多以素麵為主. 其工藝的特徵是單向鑽孔, 留有毛邊. 薄片切割的精美玉刀是代表作.古方認為”就目前考古資料而言，齊家文化玉璧和玉琮主要發現於中國西北地區的甘肅、青海和寧夏的齊家文化遺址和墓葬中，其中以甘肅最多。甘肅出土地點有：靜寧縣治平鄉後柳溝村、靜寧縣深溝鄉晨光梁、定西市團結鄉高泉村、定西市安定區內官營鎮四月八山和清溪村、定西市安定區三十里鋪、武