sableward aaa thank you so so much!!! i'm so happy with it :DDD
honestly i think it's just like. hot water mixed with dry herbs/spices. how mine works is that the base heats up and there's a little bowl which i poured water in and then dropped the prepackaged herbs/spices in. it's sort of like scented wax melts but more natural.
i think you could probably make one using a candle instead of an electrically heated base? but i've also heard of people just putting a pot with cinnamon sticks and some other stuff on the stove!
i've also just looked on ebay and there are tons of other designs from this brand! just look up "rival potpourri crock". they're all quite vintage looking though haha. they seem to average around $25 (but shipping is INSANE for me and i live in canada)