12 
 1 
Hexagonal Ice Prism.xsh
Hexagonal Ice Prism
Water-Ice.xmt
random.xng
 1.31
 16777215 
FFFFFF
 40 
 2 
 .8
 2 
Hexagonal Ice Prism.xsh
Hexagonal Ice Prism
Water-Ice.xmt
Horiz column 1 deg disp.xng
 1.31
 16777215 
FFFFFF
 22 
 2 
 2
 3 
Hexagonal Ice Prism.xsh
Hexagonal Ice Prism
Water-Ice.xmt
plate 1 deg disp.xng
 1.31
 16777215 
FFFFFF
 35 
 2 
 .3
 4 
Hexagonal Ice Prism.xsh
Hexagonal Ice Prism
Water-Ice.xmt
Parry 1 - 1 deg disp.xng
 1.31
 16777215 
FFFFFF
 3 
 2 
 2
 5 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 6 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 7 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 8 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 9 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 10 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 11 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 12 

no selection
Water-Ice.xmt
no selection
 1.31
 16777215 
FFFFFF
 0 
 2 
 1
 18
 5             30000000      256           6 
 7952945 
 2             8             0             45 
Type9
 14737632      0             9843250       0             16777215      0             16777215 
 2 
 7.3           .39           1
False
True
False
True
"1"
"not tested"
"3,4,5,6,7,8"
"2"
"2"
 50
 45            0
 1
 1             1             0             0 
 3 
 420           0             510           1             600           0.4           680           0 
 1             1             1             1             1             1             1             0             1             1 
 1             1             1             1             1             1             1             1             1            42
*#*#*#*#*#* description follows *
The most beautiful and purest coloured of the halos.  It partly circles the zenith but never completely.

The simulation is a split-sky filtered fisheye view.   The zenith is at centre.

Plate crystals falling with their large prism end faces horizontal form the CZA.   Sunlight enters the top horizontal face - numbered one - click 'Crystal View' on the ray filter panel to see the crystal - and leaves through one of the six vertical side faces.   The ray filters are set to transmit only these rays.

Change the solar altitude and see how the appearance of the CZA alters.    What is the maximum solar altitude that the CZA can be seen?

The simulation inludes some poorly oriented crystals to form the 22 degree circular halo and singly oriented columns which produce the Upper Tangent Arc.   The plate crystals form the parhelia and most of the parhelic circle.   

Turn off the ray filters and run the simulation again to show the CZA in the context of the other halos.