From Astroneer Wiki
Each Resource in the game has a certain value when it is traded, based on its rarity as listed below:
|Rarity||Resources||Cost to Purchase||Sale Value|
|Common||Compound, Resin, Organic||2||1|
|Uncommon||Laterite, Malachite, Hydrazine||4||2|
|Rarest||Coal, Lithium, Titanium||16||8|
Each item is sold for half the value it costs to purchase. For example, 1 laterite costs 4 compound to purchase but will only sell for 2 compound.