A more familiar common use is in silver-coloured modern circulation coins. A typical mix is 75% copper, 25% nickel, and a trace amount of manganese. In the past, true silver coins were debased with cupronickel. Despite high copper content, cupronickel is dark bronze in colour when in storage, but is a light copper colour when polished. Thermocouples and resistors whose resistance is stable across changes in temperature contain the 55% copper-45% nickel alloy constantan.
For the past 3 months, I've been taking several popular nootropics in relatively recommended dosages. The results have been generally positive (mental stamina, desire to learn, impressive thoughts at times), however, I am experiencing the following unwelcome side-effects. -Rash and skin irritation.
Side Effects. Headache, tiredness, nausea, vomiting, dry skin, diarrhea, or trouble sleeping may occur. If any of these effects persist or worsen, notify your doctor. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.