How do the thermal expansion rates of marble and granite compare in planters?
When selecting stone planters, understanding thermal expansion rates is crucial for long-term durability. Marble and granite, both popular choices, react differently to temperature changes. Granite has a lower thermal expansion rate (approximately 4.5–8.0 x 10^-6 per °C) compared to marble (5.0–12.0 x 10^-6 per °C), making it more stable in fluctuating outdoor conditions. This means granite planters are less prone to cracking or warping under extreme heat or cold, while marble may require more careful placement to avoid stress damage. For outdoor use in variable climates, granite is often the safer choice due to its superior resistance to thermal expansion.
