Colours are wonderful! i first discovered them when people where talking bout aura's and started looking at gemstones... i then moved on to  an interest with reiki, i got atuned to reiki level one and there learnt properly how to self meditate on the course.
Ever since then i have always seen colours when i close my eyes and/even go into deep relaxation.
the other thing i learnt when your in such a relaxed state them colours will makes shapes and objects all meaning things - a bit like dream interpretation.
sometimes you just see circles or a blurs
the colours you see are meant to be in relation to the charka yes - so blue is your throat meaning communication.. purple is your third eye - your brain. etc etc...
how i understand wether this is right or just my interpretation.
but as i said deep relaxation/mediation this is normal for when you close your eyes.
other people more atuned and very into therapies and chakra's. can see people aura's a colour around the person/body. without closing their eyes.
all lovely and soothing. i love seeing the colour purple.. amazing and when i see the colour blue i know i need to open up more and talk :)
really hope this has helped you.