As someone who is obsessed with textures, I'm so glad I discovered a little thing called oobleck. The name sounds like a lamp or bookshelf from Ikea, but it is actually a substance that can be poured like a liquid, and acts like a solid when you compress it.
It's super fun to play with - albeit messy. It is the perfect combination of liquid, solid and sheen; it photographs really well. As a bonus, it is incredibly easy and cheap to make; all you need is cornstarch, water and food coloring.
Mix the cornstarch and water together in a ratio of about 2:1; continue to add more water or cornstarch to make your ideal consistency. Once it is mixed you can add in any amount or combinations of food colorings. Because of its white color, it is easy to make pastel oobleck. It almost looks good enough to eat, but try to avoid this.
Here are some photos of the process. Happy ooblecking!