“Good things come in small packages” – such is the case with apatite. Although seldom seen in jewelry stores, and despite its small size, this stone is popular with buyers for its wonderful clarity and colours.
The Spanish call apatite the asparagus stone, for its in a range of good-looking pure transparent colours, in shades of blue, greenish yellow, greenish blue, soft pink greenish yellow colour. On the whole, blue is the most popular colour and sells the best. However, the recent availability of a neon blue-green apatite from Madagascar has created enormous interest, as it imitates the colour of neon paraiba tourmalines. Fine-quality pink apatite from California is on the market, and chatoyant blue and greenish yellow cabochons containing fibrous inclusions can also be found.
Apatite has medium dispersion and a glassy lustre that produces a bright, lively gemstone. However, gem material can often be marred by the presence of numerous inclusions, which typically are in the form of black carbon specks, tiny cloudlike inclusions, melt inclusions and “silk” (a “reflection of fibrous inclusions creating a silklike appearance). The included parts of the rough material are cut away to obtain clean faceted gemstones, resulting in small-sized stones. Burmese blue apatite displays strong dichroism, showing two colours (blue and weak blue or colourless).
Treatments and imitations
- The name apatite, which derives from the Greek for “deceive,” was given because the stone is easily confused with other minerals, such as precious beryl, topaz, zircon, tourmaline and sphene.
- Synthetic apatite has been manufactured.
- Apatite is often heat treated specifically to improve the colour and remove the silklike inclusions.
Apatite is valued in terms of colour saturation, clarity and size. The intense blues, blue-greens and violets are the most sought-after Colours and the most expensive; they will be priced on a level with clean faceted tourmaline (not paraiba). Larger sizes cost more because they are rare, and natural colours will have a higher value than heat-treated stones.
Working with apatite
- Apatite has imperfect cleavage and a conchoidal, uneven fracture, making it quite brittle. It is t also fairly soft, so avoid rough handling and be careful with facet edges and any sharp corners. In other words, treat it like an opal.
- Apatite is highly sensitive to heat, so take care during polishing or soldering and don’t use steam or ultrasonic cleaners. Cutting apatite is not easy as undue pressure or heat can cause a cleavage plane to run or open up. It is also a difficult material to polish; the corners can chip easily and scratches are hard to remove. Because of these problems, a well-cut and well-finished stone will be more valuable.
- Apatite appears in bead form in a range of colours and qualities. Unfortunately, the quality of the cheaper beads can be very poor, and they may be broken, cracked or chipped and often have damaged drill holes. The fragile beads are crushed beneath heavier beads during transportation and they become damaged when strands rub together as they are being viewed. Poor-quality apatite beads can also break when they are being strung; knot between each bead to prevent damage.
- It would be tempting to dismiss apatite as a jewelry stone because of the extra effort it requires. However, the purity of colour, especially of the blues and blue-greens, is difficult to find in other gemstone material. Use good-quality, well-made material and check the goods carefully before buying.