维尔纳叶法合成刚玉是目前市场上最常见的，因此，弧形生长纹和气泡是宝石学家进行鉴定时重要而有力的关键依据。

Verneuil synthetic corundum is by far the most common in the market. Thus it is vital that gemologists are familiar with the key identifying features - curved growth lines and gas bubbles.

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找一个圆盘，在已剪出的一对弧形布片上划出波浪纹边，前剪出波浪纹边。

Grab a plate and trace half-circles along the curved edge of each pair of wing pieces and cut out.

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它是由梳柄、梳体、直梳齿、弧形梳齿、梳齿端、防滑纹成，其特征是弧形梳齿、梳柄上刻有防滑纹、梳齿端上末端呈圆形。

The utility model is characterized in that the arc-shaped comb teeth and the comb handle are carved with the skidproof grains and the upper ends on the ends of the comb teeth are made into circles.

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