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From time to time and in different parts of the world people discover surprising remains of ancient creatures. So it was, for example, a few decades ago in one[on|in|of|about] the advanced countries. Dinosaur bones with particles of gemstone were found. After careful examination of the sparkling blue and green remains of the spine, the scientists[have announced|announced|was announced|had announced] the conclusion to which they came. For millions of years, the remains had been subject to opalization. This word is used to describe the process of replacing organic residues with opal particles. The findings[were|was|are|is] then placed in the local national museum.

However, a few years later, the bones were thoroughly[studied|studying|studies|study] again. To the surprise of the members of the scientific community, it turned out that in addition to their unusual colour, the bones are special for one more reason.

To analyze these unique fossils of the ancient creature, the scientists used a CT scanner. That machine showed that the remains belonged to a previously unknown dinosaur. Later, palaeontologists unearthed the remains of several more dinosaurs presumably of the same species, among which were the cubs. According [of|about|in|to] the scientists, all of those dinosaurs were probably united in a herd, so they died in the same place.