Slc. Roblar 'Pololei Orange' (Slc. Tangerine Jewel x C. aurantiaca) produces clusters of up to 6 flowers, each about 2 1/2" across.  Brilliant orange flowers with deep yellow in the throat.  Often blooms twice a year, most heavily in the spring.   The plant growth is almost miniature, about 6-8" tall under our conditions.  Great for growing under lights or in a windowsill.