Are you talking trichomes or pistils?? Because these are two very different things. The pistils are your "hairs" and the trichomes are the "crystals". If your pistils are still all white, you have closer to 4 weeks to finish. If all of your trichomes are white, I am assuming you mean cloudy, you can pull anytime you want. The cloudy trichs will give a more up high, and the more amber there are the more couchlock the stone will be. I usually harvest when 25-50% of the trichs have turned amber. This is usually when about 80% of the pistils have changed.
The trichomes start out perfectly clear, then go milky, finally they begin to turn amber. If ur in week 9 of flowering, i'd expect to see em changing soon, probly in a week or two. Just be patient, it'll be worth it in the end