delivered the opinion of the court:
Defendant, Tony Jones, was arrested for the possession of five separate packets containing a white rocky substance which the police believed to be a controlled substance. The State selected two of the five packets and tested their contents. The contents of the remaining three packets were not tested. Results of the two packets tested showed the presence of cocaine. Notably, the two packets tested weighed a combined total of 0.59 grams while the total weight of all five packets was 1.4 grams. Defendant was tried and convicted of possession with intent to deliver 1.4 grams of cocaine, a Class 1 felony. 720 ILCS 570/401(c)(2) (West 1992). The appellate court reversed, finding that the evidence only supported defendant’s possession of 0.59 grams of cocaine, with intent to deliver, a Class 2 felony. 720 ILCS 570/401(d). (West 1992). Accordingly, the appellate court reduced his conviction from a Class 1 to a Class 2 felony and reduced his sentence from six years to four years. 276 Ill. App. 3d 926. We affirm.
ANALYSIS
When a defendant is charged with possession of a specific amount of an illegal drug with intent to deliver and there is a lesser included offense of possession of a smaller amount, then the weight of the seized drug is an essential element of the crime and must be proved *429beyond a reasonable doubt. People v. Williams, 267 Ill. App. 3d 870, 879 (1994). A chemist, however, generally need not test every sample seized in order to render an opinion as to the makeup of the substance of the whole. People v. Maiden, 210 Ill. App. 3d 390, 398 (1991). Rather, random testing is permissible when the seized samples are sufficiently homogenous so that one may infer beyond a reasonable doubt that the untested samples contain the same substance as those that are conclusively tested. People v. Hill, 169 Ill. App. 3d 901, 912 (1988). This rule is based in reason and practicality.
In People v. Kaludis, 146 Ill. App. 3d 888, 891-92 (1986), for example, a forensic chemist visually examined 100 tablets and determined that they had identical markings, lettering characteristics, bevelling, and scoring. Based on this visual examination, the chemist opined that all the tablets were manufactured on the same tablet press with the same set of dies. Kaludis, 146 Ill. App. 3d at 892. Subsequent chemical test results of three of the tablets established the presence of a controlled substance, which led the expert to testify that all 100 tablets contained the same controlled substance. Kaludis, 146 Ill. App. 3d at 892.
However, when such samples are not sufficiently homogenous, a portion from each container or sample must be tested in order to determine the contents of each container or sample. See People v. Williams, 267 Ill. App. 3d 870 (1994); People v. Young, 220 Ill. App. 3d 488 (1991); People v. Hill, 169 Ill. App. 3d 901 (1988); People v. Games, 94 Ill. App. 3d 130 (1981); People v. Ayala, 96 Ill. App. 3d 880 (1981). In the instant case, defendant possessed five packets, each containing a white rocky substance. While the chemist looked at all the packets and weighed them individually, she selected only two packets for chemical analysis. The two packets tested showed the presence of cocaine and weighed a combined total of 0.59 grams.
*430"What inference can be drawn concerning the composition of the three packets not tested? Without more, the answer is none at all. And in this case, the five packets containing loose substances cannot be equated with identically marked and stamped tablets, pills, or capsules. While it is not difficult to speculate, as did the trial judge, that the remaining three packets may have contained cocaine, such a finding must be based on evidence and not upon guess, speculation, or conjecture. Quite simply, the chemist failed to test a sufficient number of packets to prove beyond a reasonable doubt that defendant possessed one gram or more of cocaine.
Look-alike substances (pseudo narcotics) are sold with such regularity that the legislature has drafted a criminal statute proscribing their sale. 720 ILCS 570/ 404 et seq. (West 1992). Whether the untested packets in the instant case may have contained cocaine or mere look-alike substances is pure conjecture. The State was in the best position to answer this question; it had the seized packets and could have easily tested a sample from each. This it did not do. Thus the State did not meet its burden of proof of guilt beyond a reasonable doubt as to the untested packets.
Accordingly, the appellate court’s judgment reducing defendant’s Class 1 felony to a Class 2 felony and his sentence from six years to four years is hereby affirmed.
Appellate court judgment affirmed.