AI – ‘Dating ancient art and architecture relies on a combination of absolute scientific techniques (providing specific dates) and relative methods (establishing chronological order). The most common methodologies include Radiocarbon Dating for organic materials, Dendrochronology (tree-ring analysis) for wood, Thermoluminescence for ceramics and pottery, and Archaeomagnetic dating for hearths and kilns. 

Here is a breakdown of the key methodologies:

1. Absolute Dating Techniques (Scientific & Physical Analysis)

These methods provide a specific calendar year or range. Radiocarbon (C) Dating: Used on organic materials like wood, charcoal, bone, shell, or pigments in paint. It measures the decay of carbon-14, which stops being absorbed when an organism dies, and is effective for materials up to 50,000–60,000 years old.

• Accelerator Mass Spectrometry (AMS): A refined form of radiocarbon dating requiring much smaller samples.
• Dendrochronology (Tree-Ring Dating): An extremely precise method that matches tree ring patterns from timber in buildings to established regional chronologies to determine the exact year a tree was cut down.
• Thermoluminescence (TL): Used for dating ceramics, pottery, or burnt clay/stone, this method measures the light emitted by electrons released from crystalline minerals when heated, indicating the last time an object was fired in a kiln.
• Optically Stimulated Luminescence (OSL): Used for sediments and pottery, it determines the last time grains were exposed to sunlight, useful for dating when a site was buried.
• Archaeomagnetic Dating: Measures the magnetic properties of iron-bearing, superheated materials like clay hearths or kilns, which record the alignment of the Earth’s magnetic field at the time of firing.
• Obsidian Hydration: Measures the thickness of the hydration layer (water absorption) on broken obsidian surfaces to date stone tools. 

2. Relative Dating Techniques (Contextual & Stylistic)

These methods order objects in a sequence, determining whether they are older or younger than others. 

Stratigraphy: Based on the “law of superposition,” this assumes that deeper layers of soil (strata) at an excavation site are older than those closer to the surface.

• Typology and Seriation: Organizes artifacts (e.g., pottery, statues) into a sequence based on changes in their style or frequency over time. For example, simple pottery styles often precede more complex ones.
• Cross-Dating: Uses well-known, independently dated artifacts found at one site to date similar, undated artifacts found at another.
• Terminus Post Quem (TPQ): “The date after which.” It identifies the earliest possible time an artifact could have been deposited, often used when an artifact of a known, later date is found in an older layer. 

3. Application to Art and Architecture

• Architecture: Heavily relies on dendrochronology for wooden beams and radiocarbon dating of charcoal/organic material found in foundational layers. Architectural styles (e.g., column types, masonry, roof pitches) are also compared.
• Ancient Art/Ceramics: Thermoluminescence is key for dating fired clay (pottery, terracotta statues). Radiocarbon can be used on organic pigments or charcoal within rock art.
• Historical Documentation: In some cases, inscriptions, coins, or written records found within a structure provide a precise date for the building or artwork. 

Archaeologists often use Bayesian statistical modelling to combine these different techniques, increasing the accuracy of the final dates.’