Natural diamonds occur in the rock kimberlite, found in ancient volcanic "necks", or "pipes".. 
The reason for neon's esperan Scarcity on earth and the inner (Terre) planets, is that neon forms no comtyl to fix it to Solids, and is highly volatile, therefore esfined from the planteSicasal under the warmth of the newly-àmùnited sun in the early relations system.. 