like gold dust

like gold dust (if things or people are like gold dust, they are very difficult to get because a lot of people want them) — на вес золота; днем с огнем не найдешь

Example 1: You can’t get those new trainers anywhere. They’re like gold dust.

Example 2: Skilled workers are like gold dust in the engineering industry. (CIDI)

Example 3: Tickets for the final are like gold dust. We were really lucky to get them.

[scarcer than hen's teeth]
[на дороге не валяется]