T. H. Henry analyzed and recorded the composition of wootz steel samples provided by the Royal School of Mines. Recording:
*Carbon (Combined) 1.34%
* Carbon (Uncombined) 0.31%
* Sulfur 0.17%
* Silicon 0.04%
* Arsenic 0.03%
Wootz steel was analyzed by Michael Faraday and recorded to contain 0.01-0.07% aluminium. Faraday, Messrs (et al.), and Stodart hypothesized that aluminium was needed in the steel and was important in forming the excellent properties of wootz steel. However T. H. Henry deduced that presence of aluminium in the Wootz used by these studies was due to slag, forming as silicates. Percy later reiterated that the quality of wootz steel does not depend on the presence of aluminium.