The Fact that you said the seed was black makes me wonder if its a viable seed, or one that was crushed in the packing process.

I Find a good way to start a seed is on a slow weekend. On Thursday put some water in a coffee mug, put your seeds in there, and try to manipulate them so that they arent really touching, though it does not matter much. Put the coffee mug on the stove were your pilot light is located, remember to take it off before any cooking or baking.

The seeds typically pop in a day or so, though taking 3 days is not unheard of. If your seed has not shown any root in 3 days, either change the water so it does not become stale, or get more seed.

Another thing. I have a current vegging project that we started a few weeks back. I started them all in those tiny one ounce cups that you would get a jello shot in. about 40 or so seeds straight in soil, good germ rate. I would only suggest that you avoid letting your soil DRY, but don't keep it soaking.

Don't wait too long though, although some seeds take a long time to finally pop, waiting that 3 weeks is time you could have spent growing an more eager or genetically advantaged plant.