5 GETTING ST AR TED in place with all exposed surfaces sandblasted to etc h aw ay the P or tland cement This treatment lef t the aggreg ate pebbles in relief and brought out their indi vidual tones and textures The gravel in the concrete came from the food plain of Boulder Creek a shor t distance south of the building It consists of roc k fragments torn from the giant mountains by glacier s frost running w ater and other mec hanical weathering processes then worn and rounded during their journey to the plains via Boulder Creek and its tributaries V ir tually all the roc k types that mak e up the Colorado F ront R ange can be found in the w alls Nat urally fragments of the harder and more durable roc ks and minerals predominategranite gneiss quar tz c her t and the lik e But it only tak es a lit tle looking to fnd specimens of redbrown shales and sandstones of the Flatirons of blac k obsidian glass from extinct v olcanoes and of ancient mica sc hists that were once sediments and were squeez ed and contor ted very early in geologic history There are even a few minerals of copper and other ores to be seen in places though we have yet to fnd a nugget of gold As if to pro ve that geology is up to date there is at least one fragment of manmade porcelain embedded in the lobby foor P erhaps it w as once a dish in some prospector s cabin in the early days of mining in Colorado Nature The Original Artist A few of our ar t objectsag ate petrifed wood and other shave been sawed and polished to spotlight their natural beauty Or they were prepared for special purposes suc h as the sandblasted carving of the S ociety seal or the sundial All of our natural sculptures however are truly formed by nature Y ou see them just as they came from the ear th with all of the shaping carving and polishing done by wind or running w ater working with gravel sand or silt as natural tools W all adornments throughout the building are not just decorati vethey have stories to tell F or example the roc k slabs with dinosaur trac ks tell of the time when these mighty creatures ruled the Ear th while the fossil fsh from the Eocene Green Ri ver of W yoming outside the second foor Council R oom remind us of the impor tance of the sea and marine life throughout geologic time The beautiful fligree of nati ve copper on the Council R oom w all affrms our appreciation of the mineral resources of our planet One thing is sure nestled in the F ront R ange of the R oc k y Mountains our building and its man y geological specimens and ar t objects tell a story of Ear th in its ever c hanging and aweinspiring glory