This is a beautiful dream and it's wonderful you remembered it. Because the dream is set in black and white, it exaggerates the blue color of the stone, making it stand out and have more significance. Dreams EXAGGERATE to get our attention. If dreams were common, ordinary it's less likely we would pay attention and wonder what the meaning of it is.
The dream stage or setting is a green field of grass with trees . That relates the dream to your GROWTH and HEALING and your relationships with friends and evolving. Girls and boys dresses properly and nothing to distract. Stones, gems and jewels in dreams represent our special gifts and talents. Can be representing psychic gifts, such as natural healing abilities or other spiritual gifts, as well as talents and mastery earned through previous lifetimes. A stone has memory of our history. The color was blue. electric blue could suggest a religious purity or affinity as well as spiritual power as well as peace.
It's electric color as described could suggest it's relationship to chakras. Color does heal and color does have power. It's no coincidence that you feel one way or another when around certain colors.
I would think this dream is a REMINDER for you that you were born with certain spiritual gifts or talents that could help others to evolve as well as self. There is a wonderful book out there on colors by Edgar Cayce. Well worth the purchase and seeking it out. Also any books by Charles Leadbeater...he wrote many books of colors, auras and such.
I hope you keep a dream journal!