You have alluded that the 39-D that you have in a folder is a high grade example, MS66? MS67? When you say folder, I am hoping you mean album, like a Dansco. But even in a Dansco, you risk causing damage to the coin from the acetate slides. Furthermore, without having the coin graded, you run the risk that your grandchildren will not realize the value of the coin and may potentially sell it for pennies on the dollar. Just some things to think about.