Approximately 80 percent of the wicks manufactured in the United States are made of all-cotton or cotton-paper combinations. The remainder are primarily metal- and paper-cored wicks.

Lead wicks were banned from the U.S marketplace in 2003, and for several years before that were found primarily in inexpensive foreign candle imports. NCA-member manufacturers voluntarily discontinued using lead wicks in the mid-1970s, and in 2000, asked all U.S. candle manufacturers to join its members in signing a formal pledge not to use lead wicks.

The metal-core wicks sometimes found in candles are typically zinc- or tin-core wicks. They are most often used in container candles and votives to keep the wick upright when the surrounding wax liquefies. Scientific studies have repeatedly shown both zinc- and tin-core wicks to be safe.

Most high-quality wicks are made from braided, plaited or knitted fibers to encourage a slow and consistent burn. In general, twisted wicks are of lower quality than braided or knitted wicks. They burn much faster because their loose construction allows more fuel to quickly reach the flame. However, twisted wicks are useful for certain applications, such as birthday candles.

In general, wicks can be divided into four major types:

Flat Wicks. These flat-plaited or knitted wicks, usually made from three bundles of fiber, are very consistent in their burning and curl in the flame for a self-trimming effect. They are the most commonly used wicks, and can be broadly found in taper and pillar candles.

Square Wicks. These braided or knitted wicks also curl in the flame, but are more rounded and a bit more robust than flat wicks. They are preferred for beeswax applications and can help inhibit clogging of the wick, which can occur with certain types of pigments or fragrances. Square wicks are most frequently used in taper and pillar applications.

Cored Wicks. These braided or knitted wicks use a core material to keep the wick straight or upright while burning. The wicks have a round cross section, and the use of different core materials provides a range of stiffness effects. The most common core materials for wicks are cotton, paper, zinc or tin. Cored wicks can be found in jar candles, pillars, votives and devotional lights.

Special and Oil Lamp Wicks. These wicks are specially designed to meet the burn characteristics of specific candle applications, such as oil lamps and insect-repelling candles.

The aroma from a lighted scented candle is released through the evaporation of the fragrance from the hot wax pool and from the solid candle itself. Like unscented candles, properly-formulated scented candles will primarily produce water vapor and carbon dioxide when burned. The only difference is that a fragrance is also released with a scented candle.

Most scented candles contain a combination of natural and synthetic fragrances These fragrance materials may be derived from essential oils or from synthetic aroma chemicals. A well-made candle will contain only fragrance materials approved for candle use; the addition of fragrance to a candle formulation should be carefully monitored to ensure that the candle will burn cleanly and properly.

Candle manufacturers can select from an estimated 500 to 800 aroma chemicals and essential oils to develop scents that are both pleasing to consumers and compatible with candle use. These fragrance materials are safe, high-quality ingredients that are also found in many perfumes, bath soaps, lotions and shampoos.

Various health and safety tests are conducted on the raw fragrance materials that are used in candles and other consumer products. Reputable candle manufacturers use only expertly-formulated fragrances specifically approved for candle use.

Candles are available in a seemingly endless palette of colors, from luminescent shades of ivory to deep rich jewel tones, pastels, metallics and chromatic layers.

In addition, candle manufacturers introduce new hues and shades each year, reflecting the emerging color trends in interior design and fashion.

Although candle color is the second-most important factor (after fragrance) for influencing consumer purchasing decisions, color and fragrance are closely linked. In fact, research has shown that consumers expect the color of a scented candle to mirror their psychological perception of the fragrance. A cinnamon-scented candle, for example, is expected to fall somewhere in the red-bronze palette, while "mountain breeze" draws expectations of a candle in the pale blue or green shades.

Reputable candle manufacturers must combine the art and beauty of color with the science of candle formulation to develop aesthetically pleasing candles that will burn properly and safely. Selecting the proper type and amount of colorant to use in a candle will vary according to the type of wax, wick and fragrance used in formulating the candle.

Dyes vs. Pigments

Specially-formulated pigments and dyes are used to color candles. Dyes have different properties from pigments, and are used to create different effects. In general, pigments are used to coat the outside of a candle with color, while dyes are used to color the candle throughout. 

Dyes

Available in both liquid and powder form, dyes give a candle its translucent color. Dyes also provide the candlemaker with a large degree of control over a color's shade. Because dyes are easily combustible, they will not clog a wick, and generally have a minimal effect on the burn performance of a candle.

Pigments

Pigments are microscopic, suspended color particles that create a solid wall of color, similar to paint. They do not dissolve, migrate or "bleed," and thus are not as susceptible to color fade as dyes.  Pigments usually do not burn well, and the color particles will clog a wick if burned.  This makes them unsuitable for a candle that is colored throughout and meant to be burned, but useful for coating the outside of the candle.

Both pigments and dyes are safe when used as intended, and there are no known health concerns with either type of colorant. Salt City Candle use high-quality dyes and pigments that are recognized as safe for combustion.

Colorant Formulations

Reputable candle manufacturers work closely with colorant companies to develop color formulations that will match the burn characteristics of the candle and provide the exact desired shade.

The addition of colorants will not cause a properly-formulated candle to soot. Sooting is primarily a function of wick length and flame disturbance .

Candle dyes can be affected by heat, light, fragrance and other agents in a candle. These harmless reactions can slightly alter a candle's color over time, but will not affect the candle's burn properties or safety.

About Candles

• U.S. retail sales of candles are estimated at approximately
  $2 billion annually, excluding sales of candle accessories.
• Candles are used in 7 out of 10 U.S. households.
• Candles generally can be categorized into 11 basic types: tapers, votives, pillars, container(or jar) candles, tealights, liturgical candles, outdoor candles, floating candles, novelty candles, utility candles, and birthday candles.
• Manufacturer surveys show that more than 95% of all candles are purchased by women.
• Votives, container candles and pillars are currently the most popular types of candles with American consumers.
• Candle industry research indicates that the most important factors affecting candle sales are scent, color, cost and shape.
• The retail price of a candle generally ranges from approximately 50¢ for a votive to $75 for a large pillar candle. Highly unusual or embellished artisan candles can be $200 or more.
• Two-thirds of candle purchasers say they use candles once a week or more often.
• Approximately 35% of candle sales occur during the Christmas/Holiday season. Non-seasonal business accounts for approximately 65% of candle sales.
• More than 1 billion pounds of wax are used in producing the candles sold each year in the U.S.
• Consumers are increasingly purchasing candles as a focal point for their home décor, and for aromatherapy-like relaxation and stress reduction.
• Fragrance is by far the most important characteristic impacting candle purchases today, with three-fourths of candle buyers saying it is “extremely important" or "very important" in their selection of a candle.
• The majority of U.S. consumers use their candles within a week of purchase.
• Nine out of ten candle users say they use candles to make a room feel comfortable or cozy.
• Candle users say they most frequently burn candles in the living room (42%), followed by the kitchen (18%) and the bedroom (13%).
• Approximately one in five women say they use candles to decorate the yard, patio or other exterior areas, as well as the interior of their home.
• Both men and women consider candles to be an always-acceptable and highly appreciated gift for a wide variety of occasions.
• Candle purchasers say they view candles as an appropriate gift for the holidays (76%), as a house warming gift (74%), a hostess/dinner party gift (66%), a thank you (61%) and as adult birthday gifts (58%).