Free Centennial by James A. Michener

loveliness. In autumn this valley was a place of beauty unmatched across the entire continent.
    But curiously, the valley would take its name from a much different kind of tree, which clustered on the dark south wall where the sun did not shine. It was an evergreen. Now, there were many types of evergreens in the New Rockies; they might be considered the symbolic tree of the region, but the one that grew in this valley was different, for it was not green but a spectacular blue. It was the blue spruce, a tree of dignified proportions and splendid color. It grew much taller than its neighbor across the stream, and larger. And it was not deciduous, so that in late autumn when the aspen stood bare, its golden leaves having vanished one by one, the glory of the blue spruce came into its own. In winter, when clinging snow covered the spruce, allowing patches of blue to show, the valley was a quiet, dreamlike place, so lovely that even passing animals instinctively found refuge here. Throughout the balance of the year the tall spruce trees showed noble coloring, from powdery blue to indigo.
    In historic times, the place would be named Blue Valley, a notable setting, well proportioned in all things. If it did not lie at the top of the mountains, it did not hide at the bottom, either. Its stream was capable but never turbulent, and although snow sometimes crowded the floor of the valley, it rarely fell so deep that the valley itself became inaccessible. Under any circumstances this delectable valley, with its gold and blue trees, would have been memorable, but two events made it even more so.
    When permanent ice began to form in the highest mountain valleys, it became only a matter of time until some glacier shoved its icy snout into Blue Valley. This happened, and the front edge of the glacier gouged out the bottom lands, widened the base of the valley and scoured the walls of the mountains that enclosed it. Of course, every tree within the valley was destroyed, but ages later, when the ice had receded, the trees reestablished themselves as if nothing serious had interrupted them, and the valley was now much more pleasant than it had been before, since the glacier had carved out a spacious meadow filled on the north bank with aspen and on the south with blue spruce.
    Subsequent glaciers broadened the meadow and rearranged the rocks. Each mutilated the trees, but with that fine determination which marks so much of nature, they returned, and by the year 15,000 B.C. the valley had assumed its present form and was a place of enhanced beauty.
    The second event happened long before the aspen and blue spruce had given the place its character, and we must go well back in time to understand it. About thirty-five million years ago, a pressure very deep within the mantle sent relatively small amounts of highly liquid magma probing upward at very high temperatures.
    It sought out any weakness in the structure of the rock, and was especially inclined to surge into cracks where faces met, expanding them and filling them to the remotest cranny. This had happened often before, as can be seen in any large accumulation of mountain rock: invariably the rock will show where a hot igneous material had intruded itself into interstices, and this has occurred all over the world.
    What made this incursion exceptional was that this particular flow of magma contained a high percentage of minerals, sometimes in pure state: galena, silver, copper filled the interstices. The liquid rock that crept into the long pipe underlying Blue Valley contained a large proportion of unalloyed gold.
    The end of the pipe it filled lay only ninety feet below the surface of the valley, along the northern flank. It extended downward at an angle of forty degrees for nearly a quarter of a mile. It was not a large pipe, and therefore did not contain any fantastic amount of gold, but it was substantial, and it filled every crevice.
    It lay undisturbed for more than thirty million