Aqua vs Brushed Metal
アクア / ブラシドメタル
Both sit in Apple UI, so the question is not what they belong to but how they behave. Both are read here as style. They are reached for with different intent, which is the fastest way to tell them apart.
Aqua
Mac OS X's design language of buttons you want to lick. Jelly gloss, pinstripes, deep shadows and the genie effect staged digital components as objects you could touch, and set the terms for UI throughout the 2000s. What the web made of it with images is Web 2.0 Gloss.
Brushed Metal

The hairline-metal windows of iTunes and Safari: a skeuomorphic branch that speaks an app's purpose through material, bringing pro-gear trust to the desktop.
| Aqua | Brushed Metal | |
|---|---|---|
| Era | 2000–2014 | 1999–2007 |
| Family | Apple UI | Apple UI |
| Kind | Style | Style |
| Cues | Gel-gloss buttons / Pinstriped grounds / Deep drop shadows / Metaphors of water and light | Hairline metal surfaces / Rivet-like details / Equipment metaphors / Gray tonal ranges |
| Best used for | Recreating 2000s digital culture with the texture it actually had · Making what is clickable read at once as a pressable object | Editing software for sound or video that should feel like desk hardware · Instrument and control interfaces that must read as professional equipment |
| Type | No shadow on text, weighted to stay legible over gloss | Engraved-looking light letterforms with one bright edge beneath |
| Composition | Components evenly spaced, gaps left for shadows to fall into | Knobs and readouts ranked like a device front panel |
| Material | A hard white highlight above, reflection and deep shadow below | Horizontal hairlines, gray tonal steps, small shadows building thickness |
| Caution | Gloss and shadow applied evenly to every component hides what is actually pressable, leaving texture where hierarchy should be. | Pasting the texture over every panel makes a live knob and a dead surface look like the same metal, so the controls vanish. |


