Ice Question for the Scientifically Inclined

[SkunkedAgain]

Thanks Jim, appreciate the additional insight... very interesting how the impurities aid the melting by gathering the heat... Until I got a camera, I always assumed it was dark under the ice, especially with snow on it.. but my camera has shown me how much light actually gets through the ice, so it's a lot easier to see how the solar heating is melting the ice from within... I'm learning a lot that I hadn't really considered before, but it all makes sense when you stop and think about it... I think I have forgotten or didn't learn the first time in material science what makes up a grain? I know they like to go to the space station to produce really large grain sized materials and like you mentioned the rapid cooling (quench) makes the small grain size... I just don't remember what makes grain boundaries and why can some be large or small with the same material??? I think I'd learn a lot more out of that lecture today than when I was just trying to pass the class... Guess it's time for another google search... Later J