Shoot a rock that's on every planet you land on. The whole surface of 99.9% of the planets are nothing but free ferrite dust.

3 materials are way to plenty in ALL planets, Carbon, Ferrite Dust and Silicate powder.

If you want to get tons of ferrite without really having to put in any effort, just hoard junk metal whenever you find it and refine it down into ferrite

Ok, so after posting this i found out there are a bunch of other ways to do this but i dont care because it works for begginers unlike duplicating it with the refiner

Sorry, but this is not easy and not effective, also it depends on the difficulty settings.

Just search for an airless or lifeless Planet, enter the atmosphere, fly slowly over the ground and shoot the surface/rocks from your Ship with the Photon Cannon.
Even available at your very first ship.

It acts like the mining beam.

You get a thousand times more Ferrite than this method and waaaay faster.
Also you will collect tons of Geodes, which can be transformed to Ferrite dust or sold at any space station/trading post.
This helps if you're low on money in the early game.

You can do this on any planet, but airless only have rocks, so it's the most effective way.
Don't do it on high sentinal planets, but most airless planets don't have sentinels.

If you're later in the game you can refine Ferrite from almost every material you mine.