Cornflower Blue Sea Glass
Essentially this light blue sea glass is cobalt blue without so much cobalt in the mix. Phillips Milk Of Magnesia first came in light blue before it was bottled in cobalt glass. I do have a few pieces that came from old lightbulbs in this color but the majority of cornflower blue sea glass found in Puerto Rico is from Milk Of Magnesia bottles and dates to the early 1900's.
This color of seaglass is usually considered to be much more rare than cobalt sea glass. I do not know why but in Puerto Rico I have collected more cornflower blue sea glass than cobalt.
I have wondered if this is due to the areas I favored for collecting, maybe I just got lucky! I do wonder if Phillips sent its stock of Milk Of Magnesia in the light blue bottles to Puerto Rico when it switched to the cobalt bottle as a way to clear out the old style to introduce the new one in the states.
This had improved during the last five years I lived there but before that it was common knowledge in Puerto Rico that returned, damaged, and discontinued products from the states were sent to Puerto Rican retailers.
This is a beautiful color blue. I have always called it light blue or cornflower blue. Swarovski makes a crystal color called sapphire and it is identical to this color. Czech glass makers make a glass color called sapphire as well that is a perfect match.