Primary wollastonite (wo) thought to have crystallized
from a liquid is quite rare in CAIs, having been reported in only two igneous
inclusions, White Angel and KT-1 [1, 2]. Both of these CAIs exhibit
significant mass fractionations in multiple elements and KT-1 is a FUN
inclusion, so it is highly desirable to place as many constraints as possible on
their formation. Since phase diagrams previously developed for CAIs do not
involve wo [3], we use literature data on wo-saturated and wo-free phase
diagrams in the system CaO-MgO-Al_2O_3-SiO_2 (CMAS) to establish a basic
framework for describing crystallization of wo-bearing CAIs
