Cool. It's a Japanese 'ren' character, but in this orientation:
It's commonly seen on ornamental stones in Japanese gardens (like the one above) and loosely means goodness of heart, wanting the best for others, or having humanity.
仁 in chinese means benevolence or humaneness. For example a famous quote from the Confucianist book called The Book of Rites 《礼记》“仁者人也” "ren zhe ren ye" which means "Benevolence is humanity."