Active icariin flavonols are found within the plant species known as Epimedium, and as with all plant extracts; pigment colour change between harvests is something that is completely normal. No two separate batches of finished Epimedium extract powder will ever (or should ever) be exactly the same colour/shade.
The colour of 60% icariin Horny Goat Weed extract powder will usually vary from a 'light sand' colour through to a 'solid brown' colour, the change for which is something that occurs naturally due to the following reasons:
- Geographic location of any given plant harvest.
- The proportion of each category of plant-part within the batch i.e. leaf, stem etc.
- Weather conditions and patterns occurring throughout the growth period of the harvest/batch.
- The production methods and types of equipment used during the extraction process itself.