178 JOURNAL OF COSMETIC SCIENCE Figure 1. SEM observation of tourmaline powders (x 1000). The crystal structure used was a mixture of a round-type crystal and a plane-type crystal, and had a mean diameter of 10 micrometers. The crystal structure used was a mixture of a round-type crystal and a plane-type crystal, and it had a mean diameter of 10 micrometers. The SEM image is shown in Figure 1. The chemical composition of the jade (nephrite) was Ca(Mg, Fe)5SisO22(OH) 2, and had a fibrous and planar structure. The hardness was 6 to 6.5, the specific gravity was 3.0, Figure 2. SEM observation of jade powders (x 2000). The crystal structure was a mixture of a needle-type crystal and a plane-type crystal, and had a mean diameter of 10 micrometers.

JEWELRY POWDERS AND FAR-INFRARED RAYS 179 18 16 .o_ 12 r•l 0 •- 8 ,• 6 • 4 2 0 O.25 1 3 7 Contents(%) Figure 3. The increasing ratio of radiation energy (W/m 2) of the O/W emulsion containing the tourmaline powder. The y-axis is the increasing ratio (percentlie) and the x-axis is the contents of the tourmaline powder. and the refractive index was 1.62. The crystal structure was a mixture of a needle-type crystal and a plane-type crystal, and had a mean diameter of 10 micrometers. The SEM image is shown in Figure 2. The O/W-type emulsion creams were prepared. Each of the creams contained the jade powder and the tourmaline powder. The contents of each powder were 0.25%, 1.0%, 3.0%, and 7.0% (w/w). The estimated emission energy of each cream is shown in Figure 3 for the tourmaline powder and Figure 4 for the jade powder. As shown in these figures, the emission energy increased exponentially. The increasing rate of emission energy was almost saturated at 1% content for both of the two jewelry powders. As a cosmetic ingredient, it was determined that the optimum content for each powder was 1%. 18 16 • 14 -2 12 rr10 •- 8 • 6 c 4 -- 2 0 0.25 1 3 7 Contents(%) Figure 4. The increasing ratio of radiation energy (W/m 2) of the O/W emulsion containing the jade (nephrite) powder. The y-axis is the increasing ratio (percentlie) and the x-axis is the contents of the jade (nephrite) powder.