Dugu Xin\'s Multi-sided seal 独孤信多面印
独孤信多面印 MW!
独孤信多面印是迄今发现的中国古代少有的一枚楷书印，1981年在陕西省安康市旬阳县被发现，现藏于陕西历史博物馆。质地为煤精石，呈八棱多面体，共有26个大小不一的印面，其中有正方形面18个，在14个正方形印面上刻有不同印文，可以满足不同的用途。三角形面8个。印面边长均为2厘米，通体高4.5厘米，宽4.35厘米，重75.7克。印文为楷书阴文，书法遒劲挺拔，有浓厚的魏书意趣。该印章是已发现的印面最多的中国古代多面体印章，这些印文包括了从一字印到五字印的五种印文格式，功能上则囊括了公文、上书、书信，私信等多种印章功能，反映了当时印章职能已经分化。此外，印面上共计47个印文皆为阴文楷书，表明南北朝时北方各政权通行汉字，同时它的发现证明早在南北朝时期，古人已经开始在印章中使用楷书，纠正了原先学界关于楷书入印最早为隋唐时期的观点。
(以上为网络借图，谢谢）
独孤信多面印的材质为煤精，又称煤精石、煤玉、黑玉、黑碳石等，是一种不透明、光泽强的黑色有机宝石，由碳和有机质组成，存在于沉积岩中，是远古树木在温度和压力作用下分解而成。在中国古代，有身份的文人墨客们常用煤精石制作文房用品，比如笔筒、砚台等，同时还有制作串珠、陈设品等工艺用品。但使用煤精制作印章十分罕见，所以这枚印章被直接称呼为“煤精印”。本品为现代青铜复制品，供文物爱好者欣赏把玩之用。
这枚印信的主人独孤信是鲜卑族人，先后任西魏、北周重要将领，贵族高官，史书记载他"美容仪，善骑射"。独孤信育有七女六子，其中三个女儿被封为皇后:大女儿为北周明帝宇文毓之妻明敬皇后，四女儿是唐高祖李渊的生母元贞皇后，七女儿隋文帝杨坚之妻文献皇后，其家族与中国南北朝、隋唐历史关系密切。因为独孤信有三个皇后女儿，亦被后人称为"中国第一岳父"。
印文
大司马印 大都督印 柱国之印 刺史之印 臣信上章
臣信上疏 臣信上表 臣信启事 信启事 独孤信白书
令 信白笺 耶敕 密
注：“耶敕”应该就是 “爸爸书”的意思。耶，通“爷”，父亲。
About Dugu Xin Multi-sided Seal By MW!
Dugu Xin’s multi-sided seal is a rare seal found so far in ancient China. It was discovered in 1981 at Xunyang, Shaanxi and is now exhibited in Shaanxi Museum of History.
The material of the seal is jet (a.k.a. coal jet, or coal essence). The seal is overall 45mm x 43.5mm, weights 75.7 grams, it has a total of 26 printing surfaces of different shapes, 18 square ones and 6 triangular ones, each side is 2cm equally, of which 14 square printing surfaces are engraved with different text, which can meet different purposes such as court uses, government orders, laws issuance, and personal letters. The printing on the seal is a Kai calligraphy font in Yin format (a.k.a. white letters), the text engraving skill is powerful and straight, there is also a strong influence of Wei calligraphy on the text, as Dugu Xin lived in the period when the Chinese text transformed from Wei font to Kai font. This product as pictured is a modern bronze replica.
Dugu Xin, the owner of this seal was an important general and official in the Western Wei and Northern Zhou Dynasties in ancient China at the 6th century. He was a clansman of the Xianbei tribe. History records that he was "Extremely handsome, good at riding and archery". Dugu Xin’s family had deep influences in China history during the 6th~7th century. Dugu Xin had 7 daughters and 6 sons, his eldest daughter was the wife of Yu Wenyu, the Emperor of the Northern Zhou Dynasty, and the fourth daughter is Queen Yuanzhen, the mother of Li Yuan, who was the first emperor of the Tang Dynasty, and the seventh daughter was queen Wenxian, who was the wife of Yang Jian, the first emperor of the Sui Dynasty. Because he had three queen daughters, Dugu Xin was later known as "China's first father-in-law."
The picture shows the text of each side on the seal.