I don't know about you, but apples are definitely my favorite fruit. After all, an apple day keeps the doctor away. But truth be told, it's not for their vitamins, minerals, and overall health benefits that I love a good apple. No, it's all down to my taste buds - I just love how sweet, juicy and pleasant they are to eat.

Now, in my ignorance, I used to classify apples as being either the red type or the green. But as it turns out, they are a lot more diverse than I previously thought. We might be used to a small range of different apples at our local grocery store but you probably weren't aware that there actually thousands of types available to buy.

The most common type of apples are red and green apples but black apples, a much rarer sight at the store, are increasing in popularity.

Black apples are nowhere near as common as their red and green counterparts because they are planted at altitudes of 3500 meters above sea level. Just like red and green apples, they contain many minerals and good microorganisms but they reportedly taste even better.

"The average elevation of Nyingchi, Tibet, is 3,100 meters. The temperature differences between day and night are rather big, and there is much sunlight and ultraviolet light. These unique geographical features make it the perfect natural environment for growing black diamond apples," according to Ms. Yu Wenxin, Market Director at Dandong Tianluo Sheng Nong E-Commerce Trade Co., Ltd.

Black apples, also known as scorpion fruit, do not require any fertilization. They are resistant to very low temperatures and are able to naturally protect themselves against insects and parasites. They are indigenous to New Zealand and can still be found there today, but since being introduced to China, they are also now planted at Tibet Nyingchi. They taste both crispier and sweeter than "regular" apples.

Compared to the types of apples we are used to eating, black apples are high in glucose. It's their sweet taste that is making them so popular at the moment but due to the low temperatures they require, their growth rate is pretty low.

The average apple takes 2-3 years to mature but can potentially take up to five years. Black apples, on the other hand, can take up to eight years to mature after being planted.

What's more, only 30% of mature black apples will meet the standards of color compliance. This why the total output of black apples compared to other apples is low.

Due to its exclusivity and extraordinarily high price, black apples are not the public's first choice of fruit. Fruit farmers are aware of this and so they prefer to grow other foods that have a higher demand and virtually guarantee a profit.

Chinese manufacturers have started focusing on black apples because of this very limited production. Due to their extravagant price tag, they are made into exclusive gifts and packaged in boxes to ship off to wherever they are needed. They will often be infused with black Tibetan color culture giving them more of a brilliant color. Customers will usually have to purchase them in advance to ensure they arrive on time

Would you be interested in getting your hands on a black apple for $20? It may be a pretty steep price to pay for a piece of fruit, but it might just be worth a try.