What does the carbon dating of the runestone reveal?

• A. The stone was likely carved between 1 and 250 CE
• B. The stone was likely carved in the 10th century
• C. The stone was likely carved in 500 CE
• D. The stone was likely carved in 800 CE

Answer: (B)

Radiocarbon dating tells us the age of once-living material, not the stone itself. For a runestone, the useful information comes from organic material associated with the stone—such as wood from tools used to carve it, charcoal from a forge, or organic deposits on or in the surface—that can be dated and then tied to when the inscription was made. If the dating points to the late first millennium, specifically around the 900s CE, that fits the period when runestones were commonly created, making the 10th century the best match among the options.

The other timeframes are generally outside the typical window for runestone inscriptions, so they’re less plausible given what radiocarbon dating of associated organic matter would indicate in this archaeological context. Remember that calibrated calendar dates are needed, since raw radiocarbon ages must be converted to calendar years.