Scrith is a fictional material which serves as the construction material of the Ringworld, as no known material is strong enough. No chemical substance, alloy or compound could be strong enough to hold the Ringworld together.
"Sure, it takes near-magical technology: the tensile strength of the scrith floor is about that of an atomic nucleus"
- Larry Niven
Larry Niven describes scrith as a grayish, slightly translucent material. It's surface is extremely slippery unless it has been constructed with a rough texture.
A puncture in scrith by a huge object was a plot element in Ringworld, the first book of the Ringworld trilogy (and again slighly in the third one, Ringworld throne, but not the second one, The Ringworld engineers). See Fist of God. It is debatable if meteorite is the right word for the object that caused it, as the object, most likely a large comet, asteroid or other large lump of space debris hit the Ringworld from underneath, not through the atmosphere on the upper surface.