What is the river made of in 1971's Willy Wonka & the Chocolate Factory?

What is the river made of in 1971's Willy Wonka & the Chocolate Factory?
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I'll admit it: The whimsical amusement park inside Willy Wonka's factory is exactly how I still imagine every candy factory actually being on the inside — and I've been inside very real candy factories that are nothing like that.

The 1971 film version of Roald Dahl's classic book, Charlie and the Chocolate Factory, is by far the best adaption. And I'm not just saying that because I watched it three times a year in school — I'm also saying it because of Gene Wilder.

Sorry Timothée Chalamet, but you can't beat that.

As Wonka gives a group of golden ticket holders — all children — a tour, one by one they each seem to fall prey to a vice that befits their character's traits.

One of them falls into a river of ... something. Remember what it is?

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