Wu Collection, Upper Volume
Radical: Jade (yù)
玖
Kangxi stroke count: 8
Page 727, Entry 22
Pronounced jiǔ.
In the Explanation of Simple and Compound Characters (Shuowen), it is described as a black stone, second in quality only to jade.
Book of Odes (Shijing), Odes of Wei: He presented me with a quince, and in return I gave him a piece of beautiful jade (qióng jiǔ).
Commentary: Qiongjiu is the name of a type of jade.
Explanation of Sounds (Shiwen): Jiu, pronounced jiǔ. The book states: The jade is black in color.
Also, in the Five Sounds Rhyme Collection (Wuyin Jiyun), pronounced jiù. The meaning is the same.