T&T: What Marker Is This?

[Jim Barrentine]

While passing through Hell's Gate in Georgia this week I saw a marker 
I did not recognize.  It was a diamond shape with the upper and lower 
quadrants red and the left and right quadrants white.  My 64th 
edition of Chapman's shows this on page 500 under "Aids to Navigation 
Having No Lateral Significance" and in a section called "Dayboards - 
May Be Lettered".  There were also two others shown with green 
diamonds instead of red and black diamonds instead of red.

Anyone know what this aid means and how I should have treated it?

Jim

Jim Barrentine
Endeavour Trawlercat 36 "Down Time"
11470 Euclid Ave., #404
Cleveland, OH  44106
216-496-2008
N9JKB
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