I’m fairly certain the illustrations are collage from painted paper, but it may just be a painting. The girl has either red hair or brown hair, she is naked. She is making a necklace with different items. She gets a gemstone or crystal in a cave. I believe she also collects a pebble, seashell and acorn but I’m not certain on those. I do not know what language the writing is in. I think it was likely German but maybe Swedish or Norwegian something Slavic or Germanic. I think that maybe fairies or gnomes give her the gemstone but that may be just something we made up since we didn’t speak the language. The things I’m certain of are is she goes into a cave, she is naked at least at some point and she is making a necklace.
There are several picture book versions of ‘How The Alphabet Was Made’ by Kipling. Could it be one of those? https://www.bing.com/shop?q=how+the+alphabet+was+made+picture+book+kipling&FORM=SHOPPA&originIGUID=F7272F6233A544149504C582E2EA5AD7
Alas no.