Sapphire from laos
natural no heat no treatment

as per images

Sapphires in Laos have come from great depths in the earth and are found in gem gravel created from eroded alkali basalts. In general, blue, green, and yellow sapphires from Laos have properties and characteristics similar to those of sapphires from other alkali basaltic sources. In most cases, these sapphires can be readily distinguished from metamorphic sapphires by their higher iron content. The presence of iron also influences other gemological features and characteristics such as spectra, chemistry, and the type of mineral inclusions.