Although this was a paper hit, it raised questions over trading powerhouse Glencore's largest deal to date, sealed just as the commodity cycle turns. Analysts say a strong performance on Tuesday could help perceptions of Glencore but the success or otherwise of the merger will take longer to determine. It will depend on factors ranging from market prices to the ability to retain former Xstrata staff operating the mines. "How do you prove it was a good deal? You prove it was a good deal by not only increasing the synergies, but delivering on them," said analyst Chris LaFemina at Jefferies. "You prove it was a good deal by getting a better than expected price for whatever assets you are going to sell. You prove it was a good a deal over time by operating well." (Reporting by Clara Ferreira-Marques; Editing by Anthony Barker)