It's not unusual for cilantro to take a few weeks to germinate. I'd give it another week or 2

It's unusual in MY garden for it to take so long to germinate! I'd start over.

Bad seeds? Hungry birds/squirrels? Plant new seeds.

FataMorgana

I should have mentioned when this was originally posted.

What probably did the damage was "rubbing the seeds" to "remove" the seed coat. What more likely happened is you destroyed the seed.

I don't know where this myth of having to remove the seed coat for coriander came from, but it is patently untrue and potentially harmful. I've been growing coriander for 40 years and I have NEVER had any problem germinating the seed as it comes out of the packet (or off my last planting). I get 100% germination every single time.

Someone claimed to me that if you scarify the seed coat you can get TWO sprouts per seed. This seems unlikely to me, but even if it is so, coriander seed is rather fragile, whereas seed that actually needs scarification has quite a tough seed coat. Far more likely you will destroy the seed. And given how cheap the seed is and how easily it sprouts, it's more work than its worth, even if you COULD get double seedlings from those seeds not actually destroyed in the process.

I'd call it an old wife's tale, but given that I AM an old wife and I'd never heard of this until the last couple of years, it doesn't really seem to qualify.