I am working in Pharo 6 RC, 64-bit on macOS 10.12.5 One of the tests of STON fails, #testFloat and I got confused about Floats on 64-bit Pharo 6. Is there a write-up that explains the new/changed situation ? Because, what I see is the following: Float pi. 1.3. Both the above give me SmallFloat64 instances. (10 raisedTo: 100) asFloat. 1.0e100. 10.0 raisedTo: 100. All 3 above give me BoxedFloat64 instance. But the first 2 give wrong results (correct answer is 1.0e100) ! (10 raisedTo: 100) asFloat. "5.15323791002091e91" 1.0e100. "5.15323791002091e91" Why ? BoxedFloat64 allInstances. SmallFloat64 allInstances. The first is not-empty, the second is (logical since these are immediate values). I thought BoxedFloat64 should not be used in 64-bit ? Also, should #emin, #emax and friends not be different for SmallFloat64 ? Sven