Ok, thank you. What minimum investments amount for private sale needed? And when sale ends and tokens will be trading on exchanges?
The minimum investment is 100 ETH. You can email
pledge@dusk.network with your desired allocation and they can discuss privately with you. The tokens will be unlocked after the privatesale has concluded on a Second-by-Second vesting base

Oh, 100 eth is a solid amount and its too much for me. Too bad that you will dont have public sale. Will waiting coins on exchanges

Yes, seems so that we small investors will have to wait until coins appear on exchanges but with the vesting system there won't be even a dump to buy them cheap.
If they have a bounty program, or the airdrop, then it will be possible to buy a some amount of tokens at a cheap price. This price will depend from listing, if it's will be exchange with small volumes, then the price may also fall at the beginning.