Ninja Turtles?
Gui Ban refers to the shell of a turtle, while Bie Jia refers to the shell of a soft-shelled turtle. From a broad perspective, both turtles and soft-shelled turtles belong to the reptile class, specifically the order of Testudines.
Turtles have a hard carapace (upper shell), while the soft-shelled turtle, as the name suggests, has a soft and squishy carapace. If you touch it and feel something squishy, then it's likely a soft-shelled turtle!
Furthermore, turtles have patterns on their carapace, while soft-shelled turtles typically have a plain or patternless shell.
Turtles lack teeth, but soft-shelled turtles have sharp ones.
Therefore, if it assumes a biting posture when touched, it's a soft-shelled turtle. Be careful when interacting with a soft-shelled turtle, as you might get bitten. If bitten, do not try to shake it off; instead, place it in water, and the soft-shelled turtle will open its mouth by itself.
Soft-shelled turtles have a wild, sensitive, and aggressive nature, so it's best not to touch them carelessly. On the other hand, turtles, lacking teeth, tend to hide rather than bite when they are touched.
Plate or Armour((板, 甲).
These two characters are used in the context of TCM to differentiate the two different parts of a turtle used in medicinal preparation: the plastron or the underside (板), and the carapax or the upper shell (甲).
板 (bǎn):
This character translates to "board" or "plank" in English, and can also mean "plate" in certain contexts (like a steel plate).
In the Traditional Chinese Medicine context (like in the term "龟板" or "turtle plastron"), it's used to signify a flat, hard surface, such as the underside of a turtle's shell.
甲 (jiǎ):
This character has multiple meanings depending on the context. It can translate to "first" or "best" and it's also used in naming the Heavenly Stems, a system used in ancient China for reckoning time.
In the context of "鳖甲" or "turtle carapax", 甲 is referring to an armor or a shell, specifically the hard, protective layer on top of the turtle.
Gui Ban (Testudinis Plastrum or Tortoise Shell):
Gui Ban is the plastron (underside) of the turtle. It's primarily associated with the Kidney, Liver, and Heart meridians.
This substance is typically used for yin-deficient heat conditions. It's often used to treat issues such as insomnia, dizziness, and irritability.
In TCM, Gui Ban is also believed to have tonifying properties and to aid in promoting regeneration of tissues. It's often used for conditions such as fractures, wounds, or other similar injuries.
Gui Ban is often used in combination with other herbs to enhance its medicinal effects.
Bie Jia (Trionycis Carapax or Soft-shelled Turtle Shell):
Bie Jia is the carapax (top side) of the soft-shelled turtle. It's associated with the Liver and Kidney meridians.
This substance is often used to treat yin-deficiency and to cool the blood. It's frequently used for conditions such as fever, night sweats, and hot flashes.
Bie Jia is also believed to have properties that allow it to invigorate the blood and dissolve masses, making it potentially useful for treating certain types of tumors or growths.
Like Gui Ban, Bie Jia is often used together or interchangeably.
In summary, both Gui Ban and Bie Jia are used to treat yin deficiency and heat conditions(Yang rising). The main difference lies in their other properties. Gui Ban is thought to be more useful in promoting tissue regeneration and aiding in wound healing, while Bie Jia is believed to be better at invigorating the blood and clearing heat.