Matter Block is an object unobtainable by players through normal means. This item's information is present in the game files, but not intended by developers to be in players' possession.
Matter blocks are a crafting material found inside dungeons. After picking up their first matter block players will automatically learn the crafting schematics for the three pieces of the Makeshift Armor Set.
The Makeshift Armor Set is between the tier 3 and tier 4 racial armors in strength, and can be crafted as soon as one gains access to tier 4 (Radioactive) planets. A total of 24 matter blocks are needed to craft the entire Makeshift Set. Matter blocks are also used to craft the Handy Space Helmet and the stronger Neat Welder's Helmet, which provide a greater energy increase than the Makeshift Helmet but less defense.
Matter blocks can be found on planets of tier 4 and above in Scifi Dungeons, which appear on the surface as white metal pyramids that weaken the surrounding area's gravitational pull. To obtain them, one must interact with the facility's Dispensing Pod, located in a single room within (assuming no impediments to the dungeon's generation). When used, the pod will scatter matter blocks around the room and also explode, dealing significant damage. You can double the amount obtained by removing the background in the room. After a period of time, the pod will reset, allowing additional matter blocks to be harvested. Using a mining tool on the pod will cause it to disappear and provide no matter blocks.
Once harvested, matter blocks cannot be placed. This is due to there being two different 'types' of matter blocks. The matter blocks released from Matter Generators are considered placeable blocks and have common rarity. Harvesting these blocks with a tool will cause them to drop the second type of matter block, which is considered a non-placeable item and has uncommon rarity.