Is the Hogwarts entrance letter written in the color of the receiver's eye?

Question

Reading the first few chapters of the Sorcerer's Stone, I became very curious about the Hogwarts letter over these lines.

• ...and the address was written in emerald-green ink.

• ...held up the letter so [the Dursleys and Harry] could read the green ink address...

(both from Chapter 3, The Letters From No One)

• ...the yellowish envelope, addressed in emerald green...

(Chapter 4, The Keeper of Keys and Grounds of Hogwarts)

We can see that the address of the letter that Harry received was written in emerald-green ink, which is also his eye color. However, I couldn't find out whether the letter inside the envelope was also written in green. I wonder if we can infer from this that young wizards and witches get their Hogwarts letter written in the same color ink as their eye. For example, would Ron have gotten his letter written in blue ink? If they do, the question will be How. Oh, and how will odd-eyed people's letter be like, if their right and left eye's color is different?

Answer 1

School letters (presumably from the desk of the Headmaster and Deputy Headmistress) are written in green ink as standard. Ron gets one too, as do his brothers.

‘Letters from school,’ said Mr Weasley, passing Harry and Ron identical envelopes of yellowish parchment, addressed in green ink. ‘Dumbledore already knows you’re here, Harry – doesn’t miss a trick, that man. You two’ve got them, too,’ he added, as Fred and George ambled in, still in their pyjamas.

_{^{Harry Potter and the Chamber of Secrets: CHAPTER FOUR — At Flourish and Blotts}}

Since we know that Ron's eye colour is blue, the theory that the letters are written in the recipient's eye colour is disproven.