Octahedral sulphur (rhombic or $\alpha$ -sulphur) is the most stable allotrope of sulphur. It is stable at temperature below $95.6^{\circ} C$. Its specific gravity is $2.06 .$ It melts at $114^{\circ} C .$ It is soluble in carbon disulphide. Its crystal structure contains cyclic $S_{8}$ rings packed in a manner which leads to the formation of rhombic crystals.
