Transitions, change and the passing of time:
Any material which is soluble, can be deposited as a colloid or is in suspension, or is capable of being melted, may form a stalactite. Calcium Bicarbonate solution travels through the rock until it reaches an edge and if this is on the roof of a cave it will drip down. Over time a stalactite will form. An average growth rate is 0.13 mm (0.0051 inches) a year, so these speleothems mark a long passing of time.
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