Particularly in California, before the transcontinental was built, all rail had to come via ship, and Europe and US east coast ports were effectively the same distance from San Francisco. Through the mid 1890s California was one of the most significant sources of wheat in the world, feeding much of Europe, so there were significant numbers of ships sailing from San Francisco Bay... Cargos to California were considered back hauls, with coal being used as ballast in some cases...
The Pacific Railroad Act required US manufactured rails... but non land grant railroads like the V&T or Carson & Colorado could and did use English iron. I suspect English iron was less expensive, early on due to the size of the english iron manufacturing industry.
Randy Hees
Director, Nevada State Railroad Museum, Boulder City, retired
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