Ruthenium(III) chloride is the chemical compound with the formula RuCl₃. With the CAS No. 14898-67-0,  "Ruthenium(III) chloride" more commonly refers to the hydrate RuCl₃·xH₂O. Both the anhydrous and hydrated species are dark brown or black solids. The hydrate, with a varying proportion of water of crystallization, often approximating to a trihydrate, is a commonly used starting material in ruthenium chemistry.

Preparation of Ruthenium(III) chloride: The anhydrous forms of ruthenium(III) chloride are well characterized but rarely used. Crystalline material is usually prepared by heating powdered ruthenium metal to 700 °C under a 4:1 mixture of chlorine and carbon monoxide: the product is carried by the gas stream and crystallises upon cooling.

When you are using this chemical, please be cautious about it as the following:
1. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice;
2. Wear suitable protective clothing, gloves and eye/face protection;
3. In case of accident or if you feel unwell, seek medical advice immediately (show label where possible);
4. Avoid release to the environment. Refer to special instructions safety data sheet;