Hermetise, a high-end European skin care line, reportedly uses kopi luwak (aka cat poop) as a key ingredient in its skin care line, according to Refinery29

Hermetise's Kopi Luwak Anti-Pollution Oxygen Brightening Treatment promises to give consumers an age-defying face lift with its 3-step process, which doesn't come cheap. Those willing to invest in the product can purchase the three items individually at $1,660 each or pay $4,994 for all products in the treatment. What makes this treatment so expensive?

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Kopi luwak is the most expensive coffee worldwide. The coffee's known benefits include skin firming, reduced inflammation and decreased redness. However, the creation process for this coffee is what makes it more of a rarity.

A Civet — an Asian cat-like mammal — poops out coffee cherries that are then harvested into kopi luwak. However, it's highly-valued in Indonesia because the animal is rare, rather than because of the taste of its fermented coffee. NPR reported in 2012 that the fermentation outcome somewhat resembles an "Oh Henry! bar," but they claim that it's "not even as rare as it used to be" because farmers have implemented unethical harvesting practices.

According to a press release Hermetise obtained by Bustle, "The Civet likes to eat cherry beans and while they love the taste, they are unable to break down the seed during digestion which produces a particular fermentation. When the Civet does his, 'business' what is left is newly fermented beans which farmers then collect, wash, dry, sort, and finally roast them into this expensive and extraordinary coffee."

Hermetise's treatment combines 24k gold, advanced oxygen and age-defying ingredients alongside its kopi luwak infusion to create what it describes as a strong age treatment. On the website, the brand claims the product is "designed to clear and protect skin from environmental pollutants by delivering potent film-forming, water-holding and soothing effects."

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Reviews have been left for the treatment on the product's page and appeared to show that consumers believed the kopi luwak treatment is worth the investment. Feedback on the skin care line is viewable from January 2017 onward, with no reviews hitting below four stars.

"This is my go to skincare product for a smoother, younger looking skin," one customer wrote in the reviews section. "Massaging this gel into the skin is so satisfying and relaxing. It has great age defying properties. I totally love this product because my skin has never felt this younger and radiant.."

Another customer claimed they are getting their money's worth, saying, "I have been using the product for a month now and I love the way it made my skin feel. I feel good about the product using organic ingredients and the scent being subtle but pleasant."

A third reviewer added, "Kopi Luwak Anti-Pollution cream is the new discovery for me and I loved it. The product is the best thing I have ever used. Results appear after one week."

One reviewer claimed to have "deducted" a star for presentation. The customer wrote that the product was "good and effective too. However, I deducted one star because it makes my skin a little bit greasy. Also, the product packaging doesn't look good."

Hermetise isn't the first to create a beauty treatment with feces in it. According to a report from The Huffington Post in 2012, celebrities like Tom Cruise and Victoria Beckham have discovered benefits from receiving bird poop facials.

In a related creation, YouTuber Michelle Phan also showed her followers how to make face masks out of cat litter, which reportedly makes a difference in the clearness of one's complexion.

Cat Cat, pictured July 27, 2010, feces are being used in luxury brand Hermetise's skin care line. Photo: Getty Images

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