人じん造ぞう真しん珠じゅ

Meanings

1

artificial pearl; imitation pearl

Refers to man-made pearls, as opposed to natural or cultured pearls. Used in jewelry and manufacturing contexts.

真しん珠じゅ
真珠 is a general term for pearls, including natural and cultured ones, while 人造真珠 specifically means artificial or imitation pearls.
養よう殖しょく真しん珠じゅ
養殖真珠 refers to cultured pearls, which are grown with human intervention but still formed by oysters, unlike fully artificial 人造真珠.

Compound of 人造 (じんぞう, 'artificial, man-made') and 真珠 (しんじゅ, 'pearl').