Zhè zhǒng kuàngwùzhì zài hǎishuǐ zhōng de nóngdù yuē wéi bǎiwànfēnzhīyī.
The concentration of this mineral in seawater is approximately one millionth.
Tips
grammar
Chinese fractions follow the pattern X分之Y meaning Y out of X (lit. X-divided-of-Y). So 百万分之一 = one out of one million. Similarly: 三分之一 = one third, 百分之一 = one percent.
