“dismissing any evidence that contradicts “creationism” (like “radiocarbon dating is all a conspiracy”). Give us a break.”
Carbon dating is accurate up to 5,000 years, after 5,000 years it cannot be calibrated against any historical data.
“If you want to ignore the overwhelming evidence in support of the evolution theory, fine. But don’t pretend you’re following any sort of scientific approach.”
Instead of pontificating the existence of the “overwhelming eveidence” in favor of evolution, please present the alleged evidence. Please do not pretend to take a scientific point of view.
You are off by an order of magnitude. The practical upper limit is about 50,000 years, because so little C-14 remains after almost 9 half-lives that it may be hard to detect and obtain an accurate reading, regardless of the size of the sample.
Science does not rely exclusively on Carbon 14 dating, though. Potassium-Argon dating is the most viable technique for dating very old archaeological materials. Geologists have used this method to date rocks as much as 4 billion years old. It is based on the fact that some of the radioactive isotope of Potassium, Potassium-40 (K-40, decays to the gas Argon as Argon-40 (Ar-40). By comparing the proportion of K-40 to Ar-40 in a sample of volcanic rock, and knowing the decay rate of K-40, the date that the rock formed can be determined.
Other reliable methods include OHD (Obsidian Hydration Dating), Paleomagnetic and Archaeomagnetic Dating, Thermo-Luminescence Dating, Uranium Series dating, and various fission-track dating methods. When used in combination these methods provide a suitable time span and an acceptable accuracy level.
Carbon dating is based on the rate of radioactive decay. It may be further verified using historical data, but it's not necessary, "doctor".