Natural Ametrine · 8.15 ct · Cushion · Bolivia · Unheated

This natural Ametrine weighs 8.15 carats and is fashioned in a classic cushion mixed cut, presenting a natural combination of light purple and light yellow colour zones within a single transparent Quartz crystal.

Measuring approximately 13.1 × 11.0 × 8.3 mm, the gemstone offers substantial depth and a balanced cushion outline. Its mixed-cut facet arrangement supports brightness while allowing the internal bicolour structure to remain clearly visible.

The gemstone displays a predominantly light to moderately deeper purple Amethyst-type colour, combined with a smaller light yellow Citrine-type zone. The purple portion is visually dominant, while the yellow zoning is most apparent toward the lower part of the gemstone.

Ametrine is a naturally bicoloured variety of Quartz (SiO₂) in which purple Amethyst-type and yellow Citrine-type colour zones occur together within the same crystal. The distribution and orientation of these zones can vary considerably between specimens and form one of the principal identifying characteristics of natural Ametrine.

This specimen is transparent and presents a clarity comparable to approximately VVS1, with only minute natural inclusions, fine growth features or subtle structural variations expected to be visible under magnification. The high clarity contributes positively to light transmission and allows the colour zoning to remain clearly observable.

The cushion mixed cut is assessed as Good, with Good symmetry and Good polish. The facet arrangement provides a pleasing face-up appearance, while the substantial depth helps retain colour concentration through the predominantly purple portion of the gemstone.

The natural colour division is less evenly balanced than in strongly split Ametrine, with the purple zone clearly dominant over the yellow zone. This produces a softer bicolour effect in face-up view while retaining the characteristic two-colour identity of the material.

There are no indications of heating and no indications of any other treatment. The gemstone is therefore presented with its naturally observed colour zoning and internal characteristics without documented enhancement.

This specimen is recorded as originating from Bolivia, the classic commercial source associated with naturally occurring gem-quality Ametrine.

With its 8.15 ct weight, high transparency and predominantly purple colour accented by a natural light yellow zone, this Ametrine offers an attractive and individual expression of natural bicolour Quartz. Its cushion proportions and clean internal appearance make it well suited to custom jewellery or a carefully selected gemstone collection.