We affirm the conviction and sentence for possession of cocaine, but reverse the conviction and sentence for trafficking in heroin. See Linder v. State, 493 So.2d 1091 (Fla. 4th DCA 1986).

In the instant case, the State failed to prove beyond a reasonable doubt that the weight of the heroin exceeded the statutory amount of four grams. The improper mixing of the contraband prior to testing lends doubt to the chemist’s findings as to the weight of the substances she received. Accordingly, pursuant to section 924.34, Florida Statutes (1985), we reverse the judgment and sentence for Count II (trafficking in heroin) and remand to the trial court with directions to enter judgment of conviction on the lesser included offense of possession of heroin with intent to sell. See section 893.13(l)(a), Florida Statutes (1985).

AFFIRMED IN PART; REVERSED IN PART; AND REMANDED WITH DIRECTIONS.