A complex of accessory minerals: ilmenite, apatite, zirconolite, chevkinite, baddeleite, zircon, thorite, pyrrhotite, orthite, monazite and others was studied in island arc quartz anorthite-bytownite gabbro-norite-dolerites of Ayu-Dag intrusion (Mountain Crimea). Obviously, the zirconolite in non alkaline magmatites was defined for the first time; its composition corresponds to zirconolite 3O; Y prevails in the first crystallochemical position. Baddeleite, zirconolite and chevkinite fix an early stage of crystallization, when Ayu-Dag magma has been not saturated by silica. Maybe, zirconolite and chevkinite are preserved in the Ayu-Dag gabbroides, because late and post-magmatic processes are low expressed. Chevkinite was partly replaced by orthite during magmatic crystallization with an increasing of silica activity. Chemical composition of zirconolite, chevkinite, baddeleite, thorite, orthite, REE-epidote, monazite is presented. The difference between composition of restite and newly formed zircon and thorite is shown.
Key worlds: island arc, quartz gabbro-norute-dolerites, zirconolite, chevkinite, baddeleite, zircon, thorite, orthite, monazite
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