His search for water (which was of paramount importance in the mind of Ibn Saud) proved less than successful. There was little water in the Hijaz and the possibility of any form of agriculture could be discounted.
An assessment of the feasibility of mining for gold was scarcely more encouraging. Although there were ancient gold mines in the Hijaz, they had been long-abandoned and the cost of re-opening them would be sufficient to deter any potential investors. Twitchell found some evidence of gold in the Nejd but he judged it impractical to extract it.
Twitchell's survey of al-Hasa was more optimistic. It seemed to the engineer that the geology of al-Hasa, which was similar to the geological profile of Bahrain, indicated that oil might well be present in commercial quantities. Knowing that Socal, the Standard Oil Company of California, had sent two geologists to Bahrain to undertake a detailed survey of the island, Twitchell recommended to Ibn Saud that, before embarking on the costly process of exploratory drilling, he should await Socal's results in Bahrain. If the Bahrain results were positive, it was more than likely that oil companies would be willing to invest in al-Hasa.