Brilliant Cut Facet Diagram

In 1919 the engineer-gemologist Marcel Tolkowsky published *Diamond Design*, deriving the round brilliant cut from first principles of optics — crown and pavilion angles tuned to trap and return light. His plates were thin black line-work on white: crown sections, pavilion sections, refraction and total-internal-reflection ray paths, dotted construction normals.

This system reissues that engineering drawing as a blueprint. The diagram inverts to luminous cyan strokes on a dark teal-blue field — all line, no fill — where 34.5° and 40.75° callouts, 58-facet geometry, and dimension figures read like a cyanotype technical print rather than a sparkling photographic render.

1919 年，工程师兼宝石学家马塞尔·托尔科夫斯基出版《钻石设计》，以光学第一性原理推导出圆形明亮式切工——冠部与亭部的角度被精确调校，用以捕获并反射光线。原版图版是白底上的纤细黑色线条：冠部剖面、亭部剖面、折射与全内反射光路，以及虚线绘制的构造法线。

本设计系统把这份工程图纸重新转译为一张蓝图。线条反相为深青蓝色技术底上的明亮青色笔触——只有线，没有填充——34.5° 与 40.75° 的角度标注、58 个刻面的几何、以及尺寸数字，读起来像一张氰版（蓝晒）技术印刷品，而非闪烁的钻石照片渲染。