It will be a matter of time, and how good that person is hiding their true self. I personally think 2–6 months would do it for sure. If you really want to know someone’s true colors I suggest talking with the person. If they only talk about themselves at length then that’s usually indicative of selfishness.

15 Simple Traits Of A Truly Good Person

• They are honest in relationships.
• They compliment others when deserved.
• They call their parents regularly.
• They are polite.
• They are kind to everyone.
• They are generous with their belongings.
• They remember their manners.
• They think of others.

Leadership Strength: How To Be True to Character

1. Be Willing to Speak Up and Take a Stand. There are people who avoid conflict at all costs, even if it means following a crowd they don’t belong to or agreeing to something they don’t believe in.
2. Defend Your Character. Life will test you, and it will test you often.
3. Demonstrate Toughness When Faced with Choices.

Answer: Streak is the color of the mineral in powdered form. Streak shows the true color of the mineral. In large solid form, trace minerals can change the color appearance of amineral by reflecting the light in a certain way.

To show your true colors means to reveal your true character, feelings, opinions, etc.

1. Usage. This idiom is always used in a negative sense, to describe someone who seemed to be a better person than they turned out to be once their ‘true colors’ came out.
2. Examples Of Use. “Mike showed his true colors today.
3. Origin.

: to show what one is really like : to reveal one’s real nature or character He seemed nice at first, but he showed his true colors during the crisis.

show (one’s) (true) colors To reveal what one truly believes, thinks, or wants; to act in accordance with one’s real personality, temperament, or disposition.

•true colors (noun) truth, personality, cards on the table, heart on one’s sleeve.