I have had a couple of experiences where I have seen a blue or green sparkle in full consciousness with my eyes wide open. The first experience was as follows.: I was in my house and I walked into my parents bedroom. I noticed my cat patches sitting on the bed. I was looking at her and thinking about how much I loved her, when I noticed her suddenly look at the corner of the room. I,being curious as to what she was looking at, looked at the corner of the room also. This is when I noticed a green sparkle in the corner of the room. It was very small, and looked similar to the kind of sparkle thing that a child would use for an art project. My cat and I stared at this sparkle for about 5 seconds before it disappeared before our eyes.
The second Experience was just the other day. I had just come in from taking my dog,lily, on a walk. I glanced into the mirror to tuck a piece of hair behind my ear. I then saw a small blue sparkle by my right ear. It flew diagonally in front of my face, and then disappeared into thin air. I have also had a couple of experiences where I thought I saw a flash of light out of the corner of my eye. When I go outside sometimes, especially when it's sunny out, I can see little white flecks, everywhere in the air. My friend says she can see them too.
I would be very interested to hear any comments that you may have, and would appreciate any theories as to what these sparks of light are. Thanks for the comments!