Does anyone know anything about this locality? The two listed minerals are calcite and baryte whereas the only mineral photo shows a riebeckite crystal. The riebeckite obviously comes from one of the alkaline pegmatites associated with the Mount Rosa granite. Calcite and baryte are not obvious associates with the granite, but rather some of the sedimentary rocks from the area?
The "21st Street" specimens were collected in July 1998 by Gary Hoffman of Colorado Springs. The specimens from the area are no longer accessible because a roadway covers the area. A road construction cut revealed the specimens. A local (Colorado Springs) mineral dealer helped collect and bring these to market. The specimens I once had consisted primarily of Calcite with some golden Barites. The geology of the area is definitely not igneous as you postulated. I can only speculate, having owned a few pieces, that the mineralization in the area is strictly post evaporative in regards to its genesis.