has it been restored?
Yes,  the Emesa helmet underwent several unsuccessful restorations, eventually it was taken to the British Museum, where a final restoration was finished
Emesa helmet
After its discovery, the Emesa helmet underwent several unsuccessful restorations. The primary problem was the oxidisation of the iron core, which created blisters and cracks in the silver covering. Immediately after discovery, the helmet was sent to Paris for restoration by "MM. André père et fils"; only light work was carried out due to the hope that the Syrian climate would help slow the rate of oxidisation, and due to limited funds, but the helmet continued to deteriorate. By 1952, the helmet was described as being significantly more damaged than it had been when excavated, and in urgent need of further work. Eventually it was taken to the British Museum, where a final restoration was finished in 1955. 
what is the emesa helmet? A Roman cavalry helmet can you please describe it? It consists of an iron head piece and face mask, the latter of which is covered in a sheet of silver and presents the individualised portrait of a face, likely its owner. when was it discovered? August 1936 what is its function? The Emesa helmet is highly functional, and was likely made for both parades and battle. where was it discovered? The modern-day city of Homs is it on display anywhere? Yes, the National Museum of Damascus.
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Emesa helmet [SEP] Restoration
After its discovery, the Emesa helmet underwent several unsuccessful restorations. The primary problem was the oxidisation of the iron core, which created blisters and cracks in the silver covering. Immediately after discovery, the helmet was sent to Paris for restoration by "MM. André père et fils"; only light work was carried out due to the hope that the Syrian climate would help slow the rate of oxidisation, and due to limited funds, but the helmet continued to deteriorate. By 1952, the helmet was described as being significantly more damaged than it had been when excavated, and in urgent need of further work.