|ȯthə|jenik adjective
or au·thig·e·nous (ˈ)ȯ|thijənəs
Etymology: German authigen authigenic (from Greek authigenēs born in that place, native, from authi there + -genēs born) + English -ic or -ous; akin to Greek au again — more at eke , -gen
: formed where found — used of mineral particles of rocks formed by crystallization in the place they occupy; opposed to allothogenic