After his marriage he lived for a short time at Penzance, and in 1808 he removed to Rivière House, Phillack on being appointed manager of the Cornish Copper Company's smelting works at Hayle.

Carne was a close observer, and paid special attention to the granitic veins of St Michael's Mount, and the vein-like lines of porphyritic rocks provincially termed elvans.

In 1816 and 1818 Carne communicated to the Royal Geological Society of Cornwall his investigation On Elvan Courses, in which he established their general characters and fixed the probable dates of their intrusion into the granite masses and the clay-slates.

This work led to the collection of Cornish minerals, which he left in his Will to the care of his daughter Elizabeth Carne, who added both local material and specimens from her travels and installed it in a dedicated museum in Penzance.

In connection with this subject Carne also examined most of the varieties of tin ore which have been found in veins, and such as are peculiar to the deposits in stream works.

In 1846 a paper was read by Carne On the Remains of a Submarine Forest in the North-eastern part of the Mount's Bay, and in 1851 Notice of a Raised Beach lately discovered in Zennor will be found in the pages of the Transactions of the Cornwall Geological Society, vol.

For many years he was the treasurer of the Royal Geological Society of Cornwall and due to his extensive knowledge of the laws of mines and minerals, and his intimate acquaintance with local usages, he was referred to in most cases of difficulty.