Description:
This Ternary Contour plot was created from a worksheet with four columns of data. The first three columns contained the ternary coordinates normalized to values between 0 and 1. The fourth column contained the Z values used for computing the contour.
The same first three columns of data (X,Y and Z) were added as a scatter plot to the graph layer.
Refer to this tutorial to learn how to create this graph in Origin.