Symbols on Navionics chip.

I just got a Navionics East premium chip for my 898. I have been looking at Shelbyville Lake in Illinois and see some little purple diamonds (a lot of them, actually) and some black and red diamonds. I have no idea what they mean and can find no information about them. Can anyone here tell me what they mean and is there a legend anywhere online that will tell me what the symbols on the chip mean? The boat ramp symbols are labled but the little diamonds are not...go figure.

Kenny ... they might be bouys :dono

Have you tried to click on them & see if a identifying menu pops up ??

Black/Red diamonds sounds like the icons for channel bouys .... the purple ones may be "no wake" bouys ??

... cp :cool: