Hotfix flat-back MC glass crystals, SS16 (Ø 3.8–4.0 mm) | Rhinestones, Swarovski etc

These MC (machine cut) crystals offer superior sparkle compared to lower-cost Asian crystals (pressed glass) and feature approximately twice as many light-reflecting facets as standard crystals. Manufacturers often package them under different brand names according to customer requirements (Aonc, DMC, Crone, etc.).

Sizes SS16 and SS20 have become the most commonly used crystal sizes. SS16 requires more detailed work but creates a lighter and more delicate visual effect.

Effects:
The “AB” designation indicates a special crystal surface treatment (Aurora Borealis). In addition to the base color, AB crystals create a multi-colored reflective surface effect. The sparkle is softer than clear crystal, but the richness of tones creates a highly valued visual result. AB crystals are often mixed with clear crystals.

Crystals with metallic coatings are opaque. This category includes: Aurum, Labrador, Jet Hematite, Silver Flare, Metallic Light Gold, and others.

Volcano is a modern crystal effect that creates a multi-colored “volcanic” appearance from within the crystal. The same stone may appear violet, yellow, green, or orange depending on the viewing angle.

Opal crystals have a soft milky appearance and are opaque.

SS16 size crystals can be applied using an iron. However, for faster, safer, and more precise application, we recommend using an applicator. An applicator heats only the crystal, not the base material, allowing accurate placement. On solid surfaces (such as phone cases, notebooks, etc.), crystals can only be attached using an applicator or adhesive.

KL24 recommends: The strongest hold is achieved with the correct adhesive. For gluing, use a gel-type instant adhesive. One of the best options has proven to be Bostik Quick Gel. Gel adhesive does not drip, dries at a moderate speed, does not harden in the tube tip, and creates a more flexible bond between the crystal and fabric. Suitable for both hot-fix and non-hot-fix crystals.

Risks when applying with an iron:

Crystals may shift from their position. Even the smallest placement errors can become visible.
The fabric may not tolerate the heat required for crystal application.

For delicate materials, ironing from the reverse side may work better — heat reaches the adhesive faster than passing through the crystal glass. First secure crystals with a small amount of instant adhesive, turn the fabric inside out, and apply heat and pressure with the iron. Always test beforehand on a sample piece of the same material.

Note: The color you see in a crystal depends greatly on the characteristics of light — wavelength, intensity, and color temperature. If you are working on an important project, observe the crystals under different light sources before use. The strongest color changes appear under UV (ultraviolet) lighting, commonly used in clubs and stage performances.