Perfect Bodies as Sol and Luna are endued with a perfect seed; and therefore under the hard crust of the perfect Metals the Perfect Seed lies hid; and he that knows how to take it out by the Philosophers' Solution, hath entered upon the royal highway;
for ---
In Gold the seeds of Gold do lie,
Though buried in Obscurity.
By the name of Luna Philosophers understand not the vulgar Moon, which also may be positive in its operation, and in combining acts a positive part. Let none therefore presume to try the unnatural combination of two positives, neither let him conceive any hope of issue from such association; but he shall join Gabritius to Beia, and offer sister to brother in firm union, that from thence he may receive Sol's noble Son.(The Hermetic Arcanum)