Oxide crystal fibers have some distinct advantages over other IR fibers in the 2 to 5 µm range. Their extremely high Mp makes them suitable for applications involving temperatures above 1200°C. They are very inert and non-toxic. However, most of the SC fibers made to date lack a suitable cladding and therefore some applications such as SC fiber lasers have been slow in coming. The emphasis in this work has been on passive SC fibers for the delivery of high power laser radiation. In principle, these fibers should have very high laser damage thresholds. This is particularly true of YAG fiber which, based on Nd:YAG lasers, should be capable of withstanding energy density produced by cw or pulsed high power lasers.