Materials are small elements that can be found from a variety of sources that can be used to maintain or enhance the abilities of your ship and SRV. They have three main purposes: Synthesis, Engineering, and unlocking specialized weapons and modules through a Technology Broker.
Materials do not take up space in Cargo Racks. Instead, materials have a separate inventory and are only stored in quantities that are small enough that they do not affect a ship's overall mass. Individual materials each have their own maximum storage capacity depending on quality: each G1 material is capped at 300, G2 at 250, G3 at 200, G4 at 150, and G5 at 100. Materials remain available when switching between vehicles, and in the case of vehicle destruction, they are saved by the pilot's escape system. Material Traders found at certain stations can exchange Materials within one category for a different quantity of another Material in the same category.
Materials can be classified into 1 of 3 categories.
Naturally occurring chemical elements.
From scanning various sources.
All Materials are sorted into different grades representing their rarity, with rarer materials providing greater effects when used. Manufactured and Encoded Materials use five grades, from Very Common to Very Rare, while Raw Materials only use four, from Very Common to Rare.
Crystalline Shards produce Crystalline Clusters which, when shot from a SRV, drop high-grade materials matching the planet's composition. In other words, they drop the same material as Needle Crystals would in a volcanic site, but there are lots and lots of them. They've been discovered in the Sanguineous Rim and beyond.