Larger | Spin | 3D. Indium foil. Indium is often used to form air-tight seals between glass components because it is soft enough to mold itself to the shape of the glass, and because unlike rubber or other organic seal materials it is really 100% gas-tight and it doesn't release volatile compounds of its own.
Melasma is a chronic skin disorder that results in symmetrical, blotchy, brownish facial pigmentation. It can lead to considerable embarrassment and distress. This form of facial pigmentation is sometimes called chloasma, but as this means green skin, the term melasma (brown skin) is preferred.
Melasma: Blotchy patches of darker color often appear on the cheeks. The woman on the right developed the brown patches while pregnant. Melasma: Signs and symptoms . Common signs (what you see) of melasma are brown or gray-brown patches on the face. These patches most commonly appear on the: Cheeks. Forehead. Bridge of the nose. Above the upper lip.