There are 38 materials in the game with the majority of them being found around many of the world locations by using gathering points but four of them must be crafted using the games recipe system at one of the games many Grimoa statues.
The items that can be found and their possible locations are as follows
Rusty Iron - Coastal Forest, Underground Channel, Desert Labyrinth, Cave of Sand
Iron - Underground Channel, Golbenia Volcano, Desert Labyrinth, Cave of Sand
Silver - Desert Labyrinth, Fire Ruins, Cave of Sand, Golbenia Volcano, Underground Channel
Gold - Desert Labyrinth, Toleno Cave, Golbenia Volcano
Platinum - Golbenia Volcano
Boar Hide- Coastal Forest, Desert Labyrinth, Fire Ruins, Forest of Springs, Golbenia Volcano
Serpent Fang - Desert Labyrinth, Forest of Springs, Fire Ruins, Golbenia Volcano
Killbear Skin - Cave of Fire, Desert Labyrinth, Golbenia Volcano
Basilisk Tusk - Forest of Springs, Cave of Fire
Hydra Bone - Cave of Fire, Golbenia Volcano
Dragonika Bough - Coastal Forest, Forest of Springs, Forest of Owls
Marmedia Leaf - Forest of Springs, Forest of Owls
Tartaros Root - Forest of Springs, Forest of Owls, Forest of Loftiness
Eyron Vine - Forest of Owls
Bosh Seed - Forest of Owls, Forest of Loftiness, Desert Labyrinth
Eden Seed - Forest of Owls, Eastern Island, Forest of Fu Plateau
Saltpeter - Desert Labyrinth, Cave of Fire, Cave of Sand, Iron Mine, Golbenia Volcano
Ruby - Coastal Forest, Fire Ruins, Underground Channel, Iron Mine, Ice Palace
Sapphire - Fire Ruins, Iron Mine, Ice Palace, Underground Channel
Emerald - Fire Ruins, Iron Mine, Ice Palace
Topaz - Desert Labyrinth, Fire Ruins, Iron Mine, Toleno Cave, Ice Palace
Amethyst - Fire Ruins, Toleno Cave, Ice Palace, Iron Mines
Amber - Fire Ruins, Toleno Cave, Ice Palace, Iron Mines
Pearl - Iron Mine, Ice Palace
Diamond - Ice Palace (Rare Spawn)
Mint - Coastal Forest, Forest of Springs, Fire Ruins, Forest of the Mind, Ancient Forest
Basil - Coastal Forest, Forest of Springs, Fire Ruins, Ancient Forest, Dolphin's Eye
Lemon - Forest of Springs, Fire Ruins, Forest of the Mind, Ancient Forest
Ginger - Forest of Springs, Fire Ruins, Forest of the Mind
Maple - Fire Ruins, Forest of Loftiness, Ancient Forest
Honey - Forest of Loftiness, Forest of the Mind, Ancient Forest
Apple - Coastal Forest, Forest of Loftiness, Ancient Forest
Shiso - Forest of the Mind
Rare Metal - Ice Palace (found in a chest)
Diamonds are super rare, it took me somewhere around 30+ runs through Ice Palace to find the four that you need (discussed below). They do exist, just persevere.
The materials that need to be crafted and the recipes to make them are as follows
Deluxe Leather - Platinum x4, Hydra Bone x3, Eden Seed x3
Blue Ruby - Platinum x4, Eden Seed x3, Diamond x3
Gold Thread - Hydra Bone x4, Eden Seed x3, Shiso x3
Silk Cloth - Diamond x4, Eden Seed x3, Shiso x3
The easiest way to make these all is to gather the minimum amount of materials you need to make the most expensive ones then save your game at a Grimoa statue craft one of the materials and reload your game. The achievement tracker will make note of your progress and this way you don't need to farm more of the harder items to find like Diamonds,
The minimum amount of materials you need are
Platinum - 4
Hydra Bone - 4
Eden Seed - 3
Diamond - 4
Shiso - 3
Once you have everything you need just save your game, craft an item, reload and repeat until you get the bleep-bloop.
Any questions or anything to add please comment or PM me directly.