Boyd’s Bible Dictionary:
Wood of the thyia, sandarac or pine variety, yielding a choice gum and hard, dark colored, fragrant wood
Indigenous to northern Africa (Rev. 18:12).
Concise Bible Dictionary:
The Greek word is θύϊνος, and occurs in Revelation 18:12 only, as being brought to apostate Babylon. It was doubtless some wood used for decorative purposes, and is supposed to be identified with the callitris quadrivalvis. It was the wood called by the Romans citrum, of which expensive articles were made. It is “sweet wood” in the margin.