Any rock can be radioactive, but igneous rocks tend to have radioactive properties because they may have radon gas trapped in their crystals. When under pressure radon gas is released from the rock. Radon gas is a radioactive gas, when it is inside the crystals of an igneous rock it will make the rock itself radioactive. It changes over time as the unstable isotopes decay, thus the amount of radioactive element goes down, but the amount of the new element goes up.
An attachÃ© is a thin briefcase used for carrying papers. It is sometimes called an attachÃ© case. You may notice that in spy movies, an attachÃ© is often swapped out by the bad guy, and then the good guy spends the rest of the movie trying to get it back. AttachÃ© comes from the French attacher, which literally means attached, and it was first applied to someone working for a diplomat, such as a junior officer. Now an attachÃ© is a technical expert assigned to the staff of a diplomatic mission.
verb (used with object) 1. to add as a supplement, accessory, or appendix; subjoin: to append a note to a letter. to attach or suspend as a pendant. to sign a document with; affix: to append one's signature to a will.