The difference is in how the balls or ends thread onto the post.
With external the Threading is on the post and the post works like a screw or male with the ball working as a nut or female.
With Internal the ball or ends has a post attached to it that is threaded. The post is counter sunk and threaded. So, the ball is the screw and the post is the nut or female. Internally Thread jewelry is more expensive but the advantages are that the since the threading is not on the post it doesn't present the risk of dislodging the piercing, it take more turns to tighten and loosen the ends so it reduces the risk of losing ends. For more information on Barbells and Jewelry go to the Jewelry Information Pages.
No, after years of spending far too much on shipping, I stopped doing special orders. However, I do suggest a couple of web sites to buy jewelry online.
Stop by the studio, I never charge for jewelry changes or removing jewelry.
Currently, the Axiom stock Implant Grade Surgical Stainless Steel and Titanium. If you are sensitive to metals your best bet would be Titanium, however often the reactions you have had in the past may have had more to do with the quality of the finish of the jewelry or the fact that the jewelry was plated or filled and not solid.
Currently, the Axiom does not stock gold jewelry. If you are sensitive to metals, gold may not be your best option though. Titanium and even Implant Grade Steel may in fact be more body friendly than Gold depending on the gold alloy. Also the amount of stress put on the jewelry's finish during the healing can often discolor gold. It's usually best to heal with a different material and then switch to gold after the piercing is healed.
I would not suggest wearing silver during the healing of the piercing at all. There is a number of issues with the softness of the metal to the alloy itself that make it a poor choice. Even after the piercing is healed, it should never be worn in areas of the body that are mucus membranes. This would include any piercing in the nose, mouth or genital area. The reason is that the jewelry could leak out silver salts, the body adsorbs it and it could lead to Argyria also know as Silver Poisoning. With piercings it will cause the area to turn blue or blue-gray. The discoloration is though to be irreversible.
I had completely removed it from my aftercare instruction for years but there is a recent trend in using silver for Septum piercings and a flood of cheap sliver rings and nostril screws being sold as "nose jewelry" that are made of silver.