WARNING: Beware of imitations. There're many other "tie zhai weng". The one sold by MasterChinese is guaranteed Shang Hai Premium. See photo.
Sign of authenticity:
1. Distinct fragrant scent instead of foul smell
2. The structure of the solid
3. The box is brownish cloth not some yellow/blue/other color paper box.
4. The characters are printed sharply, crispy clear, not smeared.
5. And of course... the quality of the result. The feeling, the final look of your calligraphy or drawing result.

Shang Hai factories have produced high quality ink known for years. This ink is one of them, type You Yan (oil soot). This is black 101.
Additional info: Oil soot has glossiness, pine soot doesn't. One usually uses oil soot to draw and pine soot to write.
Many similar items have the same name. Guaranteed original ink stick by Shang Hai factory for items sold by MasterChinese and exact item as described

Other examples: "Bai Shou Tu" is an oil soot black number 102 (ASIN: B00IXKNS9O). Huang Shan (ASIN: B00GIFH8BU) is a pine soot. For Beginners or practice purposes, one might want to check economical ink stick Shu Dao ASIN B00HBMUBNQ

• Excellent premium Shang Hai Ink stick (See photo for the name using Chinese Character)
• Guaranteed original
• Excellent for the professionals. But lucky beginners can have it too!
• Type: You Yan (oil soot) Black
• Include: 1 stick. Weight: 31g (1.1 oz)

Excellent premium Shang Hai Ink stick (See photo for the name using Chinese Character)Fortitude